1) Where is the father (or, where are the fathers)?
It seems that there were at least 2 different fathers. Had 2 children with the 1st man, didn't marry him. Then married an abusive man and I suspect had the other 3 children with him. If he was abusive, my guess is that she got away from him, and filing for any child support, 1) costs money, 2) would tell him where they are. That may be something she doesn't want.
2) If dad is dead, where is the life insurance?
No mention if either man is alive or dead.
3) If dad isn’t dead, why can’t he/they help?
See answer to #1. Mom probably doesn't want to get beat up again.
4) If dad didn’t hang around after #1, why did she have #2, 3 and 4?
#1 & #2 have same dad, #3, #4, and #5 have different dad than 1st two kids.
I am in agreement on the issue of the age of these children. They could be working to help their mother, and she isn't getting $$ for anyone over 18, but is still trying to feed them with what she does get.