1)
Why does it say "va'Yigdal ha'Yaled"?
1.
Malbim: This shows that the death was not due to weakness, that he was not properly developed [at birth]. He grew normally!
2)
Why does it mention that he went to the harvesters?
1.
Malbim (from Yerushalmi Yevamos 15:2): The sun beats down on a person's head at the harvest time.