It's such a sad story. It's easy to blame the mom. But remember, she would have been around 16 or 17 when he was born. Hardly more than a baby herself. It also sounds like from the scant details available that she does not have much family support, which often points to a poor homelife. I wouldn't be surprised if she found someone who acted like he would take care of her and desperate to escape bad situation ran to it. This is only conjecture of course.
Sometimes no matter how hard you try, things happen .It sounds like she was doing what she could. She took the steps of having the knobs on the doors, keeping the beer outside the house, etc. (if that is indeed what happened.)
I have a student right now whose mom is in prison. There are definitely a lot of issues that stem from that that have been a significant challenge this semester. And this is a family that has a very strong family support system. I can't imagine what it would be like if she was in the same situation as this little boy: young mom with seemingly no family support. I hope whatever happens they find a way to get her the suport she needs.
I didn't see anything at all in the posted article that mentioned anything about the mother not having family support or a poor home life. I even searched the internet and could find no further details about the mother or her upbringing, or anything (this was last night), so not sure how you came to that conclusion. I even watched the interview with the mother a couple of times.
As far as the mother doing 'what she could', the ONLY thing mentioned was the door safety covers. This child has a
history of running away, and if that was my child, I would have the common sense to put locks on the door that open with a key from the inside, or some sort of locking mechanism up at the top of the door where the child couldn't open it, even with a chair. Those door handle covers don't work very well, and they said the boy basically tore it off. I've had those covers, and kids can figure out how to use them even when they are on. My kids could even bypass the childproof cabinet locks.
This was probably not the first time the child has tasted beer, and it was clearly left where he could reach it.
Also, I find it disturbing that the child wants to get arrested so he can go to jail to see/be with his father. Has anyone explained to this boy (since he repeatedly does this) that jail is a very bad and scary place, and that he is too young to go to jail, and even if he did, he would not be with his father; that's not the way it works? Has anyone explained to the little boy that what his father has been doing (what lead to him being put in jail) is very wrong, and he should not try to "follow in his footsteps" and why? It appears that this boy has knowledge of things that normal boys his age don't. And his perception is warped. Four is very young, but not too young to try to explain things.
The boy has obviously witnessed some sad behavior, and I have not read anything that said the boy was in counciling, or getting professional help. How is the mother doing her best? In what way?
Another thing that made me

is this:
Why would the little boy rather be with his father in jail than be at home with mom?
I feel strongly that young girls need to be confident, have self esteem, self worth, and
educate themselves. This will help them make good choices and not play the role of the victim. I know this is not the case for many females for various reasons,and I understand that (and very hard for some). However, women should not sit back and wait for someone to come to them/help them/tell them what to do.... they need to help themselves. This can be done in many ways, and there are so many resources available---I even see pamphlets hanging in many bathroom's. There are free councilors, free attorneys, papers you can fill out to have court costs waived, womens centers that offer free classes on just about everything. I could go on and on. This mother is divorcing the father now, but maybe she should have a lot sooner. You do not need a family support system to get help. There are a lot of people out there who are there to help women and children. I don't have a family support system really, so I learned very early to be independant, and I seek out whatever I need, and help myself first.