Gemara

13b (Mishnah): The following may shave and launder on Chol ha'Mo'ed: one who came from overseas, was freed from captivity or prison, and one who was released from excommunication or whose Neder was permitted. We may launder napkins, Mitpechos Seforim, and towels. A Zav, Zivah, Nidah, Yoledes or any Tamei person who became Tahor may launder. Everyone else is forbidden.

(Gemara) Question: Why is everyone else forbidden?

Answer (Mishnah): People of the Mishmar or Ma'amad (whose week it is to be in the Mikdash) may not cut hair or launder. On Thursday it is permitted, for the honor of Shabbos;

(Rabah bar bar Chanah): This is so they will not go to the Mikdash unkempt.

Likewise, one should not enter the Regel unkempt!

Question (R. Zeira): If one was busy looking for an Aveidah before the Regel, is he permitted?

Answer (Abaye): No. Will we say that all Serikin (designs on bread) are forbidden (on Pesach, lest the delay cause the dough to become Chametz), except for those of Baisus (a baker who had molds to make designs without delay?! Likewise, we do not distinguish whether or not he was busy before the Regel.)

Question: R. Yochanan taught that one who has only one shirt may launder it on Chol ha'Mo'ed. We are not concerned for making distinctions!

Answer: Mar bar Rav Ashi taught that there, there is no concern, for his belt makes it clear that he has no other shirt.

18a - Question (R. Yirmeyah - Mishnah): The following may launder on Chol ha'Mo'ed: one who came from overseas...

One who has only one shirt is forbidden!

Answer (R. Yakov): The Mishnah forbids one who has two shirts, one of which is dirty.

(R. Yitzchak bar Yakov): One may launder linen garments during the Mo'ed.

Question (Rava - Mishnah): We may launder napkins, barbers' smocks (or Seforim covers) and towels.

We do not permit linen garments!

Answer (Abaye): The Mishnah permits napkins... even if they are not of linen.

Support (for R. Yitzchak - Bar Hedya): I saw people washing linen garments in Lake Tiverya!

Rejection (Abaye): Perhaps Chachamim disapproved.

Rishonim

The Rif brings our Mishnah and the Heterim for linen garments and one who has only one shirt.

Nimukei Yosef (DH Masnisin): The Heter for one whose Neder was permitted is when he could not find a Chacham beforehand to permit it. Mitpechos Seforim are barbers' smocks (to protect the customer's garments). The Yerushalmi forbids laundering them in urine, for it is dishonorable. It holds that they are Seforim covers.

Rejection (Tosfos 18b DH ha'Seforim): Perhaps they are barbers' smocks. It is dishonorable to launder them in urine, for they will be put on people!

Nimukei Yosef (DH Gemara): Linen garments may be laundered normally in the river, since they get dirty quickly and are easily laundered.

Rambam (Hilchos Yom Tov 7:17): It is forbidden to shave or launder on Chol ha'Mo'ed. This is a decree lest one delay these until the Mo'ed, and enter the first Yom Tov unkempt. Therefore, anyone that was unable to shave or launder before Yom Tov is permitted during the Mo'ed.

Rambam (21): A Zav, Zavah, Nidah, Yoledes or anyone who became Tahor during the Mo'ed may launder. One who has only one shirt may launder it during the Mo'ed. We may launder napkins, barbers' smocks and towels. One may launder linen garments because they need to be laundered constantly, even if they were laundered the day before the Regel.

Rosh (3:21): One who has only one shirt may launder it during the Mo'ed. The Yerushalmi permits children's garments, like one who has only one shirt. Rav Yitzchak permitted linen garments, but our custom is to forbid. One should not permit it.

Hagahos Ashri: The Heter to launder linen garments is when they are dirty. The Ra'avad says that if one has two shirts and both are dirty, he may launder only one of them.

Poskim

Shulchan Aruch (534:1): We may not launder on Chol ha'Mo'ed, except for one who came from overseas... We permit napkins, Mitpechos Seforim, towels, children's clothing, and a stain (of Dam Nidah).

Mishnah Berurah (4): Napkins are permitted because even if one laundered them before the Mo'ed, they get dirty. This is even if he has many, for a fresh one is needed each day. However, nowadays the custom is to change them only for Shabbos, so one who has two may not launder them during the Mo'ed. Handkerchiefs are like napkins regarding laundering.

Kaf ha'Chayim (7): The Shulchan Aruch did not discuss covers for Seforim. A Sefardi Sefer Torah is in a case, and we cover it only between Aliyos or during the Berachos, so we never launder the cover. Ashkenazi covers get dirty, but not so quickly, so they need not be laundered during the Mo'ed.

Mishnah Berurah (6, and more explicitly in Kaf ha'Chayim 8): Nowadays we are stringent about napkins, Mitpechos and towels.

Beis Yosef (DH u'Mah she'Chosav v'Eis): 'Anyone who became Tahor' includes one who became a Ba'al Keri or saw a stain of Dam Nidah during the Mo'ed.

Kaf ha'Chayim (10): This is only if he or she has no other garment.

Mishnah Berurah (8): Likewise, a woman who became Nidah during the Mo'ed may wash for the need of wearing white during the Mo'ed.

Shulchan Aruch (ibid.): One who has only one shirt is permitted.

Beis Yosef (DH u'Mi): Tosfos (14a DH she'Ein) was unsure whether or not we permit one who has only one shirt but did not launder it before the Mo'ed. Tosfos (18a DH Af Al Gav) permits.

Question: The Tur says 'the SMaK permits one who has only one shirt only if the belt makes this evident. Even further, R. Peretz forbids our garments (which do not have belts attached).' What is the 'further' Chidush?

Answer #1 (Darchei Moshe 5): R. Peretz forbids our garments even though they are linen.

Answer #2 (Taz 1): R. Peretz forbids nowadays even if the belt is attached, since we are not used to such garments and it is not evident to people that the man has no other shirt.

Question (Beis Yosef DH v'Nir'eh and Kesef Mishneh): Why didn't the Rif, Rambam and Rosh mention that we permit only if his belt makes it clear that he has no other shirt? (I.e. it is fixed in his shirt and he washes it with the shirt (Rashi Chulin 108a). Anyone else removes it whenever he takes off his shirt and girds it on the new shirt he wears.)

Answer (Beis Yosef): They explain like Rashi in Moed Katan (14a), that one with only one shirt girds the belt over his cloak while washing the shirt. Mar bar Rav Ashi did not give a condition for the Heter. If so, his words would have been taught with R. Yochanan's! Rather, he explained why we are not concerned for suspicion. Therefore, the Poskim did not need to mention it.

Beis Yosef (DH Ela): However, the concern exists if someone else, e.g. his wife, launders it! Indeed, perhaps he must launder it himself. The words of the Gemara, 'one who has only one shirt may launder', connote that only he is permitted. Therefore, the Poskim did not need to mention this. However, we would have to say that he may not wear a borrowed shirt while laundering, for then it is not recognizable. The Poskim should have mentioned this. We must say that if he can borrow, he may not launder. We are not concerned lest someone agree to lend him only while he launders, for this is not common.

Beis Yosef (DH v'Od): Alternatively, since one with only one shirt usually has no one else to serve him, we do not limit who may launder it.

Magen Avraham (3): The Shulchan Aruch did not specify. This implies that he permits even without a belt.

Kaf ha'Chayim (11): He may ask his wife or a Nochri to wash it, for nowadays it becomes known if someone has only one shirt.

Mishnah Berurah (9): Nowadays one who has only one shirt may be lenient only if it is of linen.

Kaf ha'Chayim (12): Maharikash permits laundering through a Nochri. Since it is needed for the Mo'ed, this is like one who has only one shirt. This is exceedingly lenient. Our custom is not like this.

Shulchan Aruch (ibid.): All of these may launder normally with soap, openly by the river.

Beis Yosef (DH Kosav): The Mordechai (873) and Hagahos Maimoniyos (100) bring from a Tosefta that even when laundering is permitted, it must be covert. For the honor of the Mo'ed it is permitted openly by the river. Bar Hedya's testimony supports this. I found that the Tosefta discusses an Avel within 30 days.

Rebuttal (Magen Avraham 4): The Tosefta also discusses shaving, and they explain that this refers to during the Mo'ed (531:5)! The Darchei Moshe (6) says that the Tosefta forbids laundering overtly, e.g. bringing it to a Nochri, for it could be cleaned as well covertly. It may be done openly if this cleans better, i.e. by the river, for the honor of the Mo'ed. However, there is no source for this. It seems that what is permitted to everyone, e.g. linen garments or Mitpechos, is permitted openly. What is permitted only to individuals, e.g. one who was overseas, must be done covertly, for others do not know that he is permitted.

Rema: They may launder only what they need, i.e. one shirt. Cloths (diapers) in which we wrap infants and they urinate and excrete in them may be laundered four or five at a time, because one constantly needs many of them.

Beis Yosef (DH u'Bigdei Ketanim): Hagahos Maimoniyos (90) and the Mordechai permit laundering children's clothing only one at a time. The Terumas ha'Deshen says that this applies to shirts, but diapers may be laundered three or four at a time, since these are needed to wrap the child. Also, they are needed for the growth of the child, and Chachamim did not decree about such things. No Heker is needed, for everyone recognizes that they are diapers.

Rema (ibid.): The Heter to launder openly is only by the river, for it launders better. Otherwise, one must launder covertly.

Magen Avraham (4): This applies even to children's clothing, because not everyone knows that they do not have more clean clothing in the house.

Shulchan Aruch (2): One may launder linen garments. The custom is not to. This is a case of something permitted which people treat like Isur. One may not permit it in front of them.

Beis Yosef (DH u'Vigdei Pishtan): The Rif, Rambam, Rosh and others permit linen garments. The Mordechai and Hagahos Maimoniyos are stringent, for Abaye and Rava disagreed. The Rosh says 'our custom is to forbid, and one should not permit'. It seems that the Tur explains that this refers also to children's clothing, but R. Yerucham says that it refers only to linen garments.

Magen Avraham (5): If people were stringent because they erred, one may permit this (YD 214:1). Here is different, because some rule like Abaye and Rava.

Kaf ha'Chayim (18): The concern is that they are stringent because their ancestors ruled like Abaye and Rava, so it is not a mere Neder.

Mishnah Berurah (14): One may give linen garments to a Nochri to launder, especially if he will launder them after the Mo'ed. One should not count the garments.

Gemara

Version #1 (Shmuel): One may shave a child born during the Mo'ed. This is the ultimate freedom from prison (it was impossible to shave beforehand).

Inference: He permits a child born during the Mo'ed, but not one born before the Mo'ed.

Question (Rav Pinchas - Beraisa): All those permitted to shave on Chol ha'Mo'ed may shave during Aveilus.

Inference: One who may not shave on Chol ha'Mo'ed may not shave during Aveilus.

If a child born before the Mo'ed may not shave, this implies that (he is forbidden during Aveilus, i.e.) Aveilus applies to a child. But this is not true!

(Beraisa): We tear the garment of a child (Avel) to make others grieve (but not because Aveilus applies to him)!

Answer (Rav Ashi): The Beraisa does not say that others (who may not shave on Chol ha'Mo'ed) are forbidden (to shave during Aveilus). Rather, some others are forbidden, and some are permitted!

Version #2 - Ameimar - (Shmuel): One may shave a child during the Mo'ed, whether he was born before or during the Mo'ed.

Support (Rav Pinchas - Beraisa): All those permitted to shave on Chol ha'Mo'ed may shave during Aveilus.

Inference: Others (who may not shave on Chol ha'Mo'ed) may not shave during Aveilus.

If a child born before the Mo'ed may not shave, this implies that Aveilus applies to a child. But a Beraisa says that we tear a child's garment (only) to make others grieve!

Rejection (Rav Ashi): The Beraisa does not say that others are forbidden. Rather, some others are forbidden, and some are permitted!

Rishonim

The Rif brings both versions of Shmuel.

Nimukei Yosef (DH Katan): Shmuel permits a child is if his hair is long and pains him. We do not fine him for entering the Regel unkempt, for he is exempt from Mitzvos, and we do not decree lest adults come to shave. Even though we reject the proof for the second version, the Halachah follows it.

Rambam (Hilchos Yom Tov 7:19): One may shave a child during the Mo'ed, whether he was born before or during the Mo'ed.

Magid Mishnah: The Rambam rules like the second version because we are lenient about mid'Rabanan laws. Also, the simple understanding of the Beraisa supports it, even though the proof was rejected.

Rosh (3:2): Even though the Stam Gemara brought the first version, it seems that the Halachah follows the second version. The reason to forbid shaving during the Mo'ed, lest one delay shaving until the Mo'ed and enter the Regel unkempt, does not apply to a child.

Poskim

Shulchan Aruch (OC 531:6): One may shave a child during the Mo'ed, even if he was born before the Mo'ed.

Beis Yosef (DH Katan): The Rif did not say which version he rules like. Perhaps he assumes that we understand that the Halachah follows the latter version.

Mishnah Berurah (15): We permit only if his hair is long and pains him. This is a need of the Mo'ed. Shaving a Nochri is forbidden like other Melachos, unless the barber has nothing to eat.

Kaf ha'Chayim (26): Most Poskim do not stipulate that his hair is long and pains him. Some infer from this that it is permitted in any case; others disagree.

Kaf ha'Chayim (28): He is permitted until he is 13 with two hairs, even if he reached the age of Chinuch.

Shulchan Aruch (ibid.): This is permitted even openly.

Magen Avraham (9): This is because everyone can see that he is a child. Perhaps if the child looks like an adult it is forbidden openly.

Gra (DH v'Afilu): We forbid something openly only if it is forbidden for other people.

Kaf ha'Chayim (30): One may delay the celebration of a boy's first haircut (Upshorn) until the Mo'ed and a Yisrael may shave him. Such a case was done in Yerushalayim for a five year old during Sukos, in a Beis ha'Keneses. Some say that the barber should be an Oni.