Until we know more, I'm inclined to be sympathetic to Leila's mother who was homeless, jobless, receiving an income of $500 a month, and pleaded to be able to talk to her kids. None of us know why he was awarded custody, but the fact remains that her income was barely enough for one person to get by. He must have known that when he went for custody, unless her situation drastically changed to due accident, addiction, or some other possibility. And even then, I'm not sure what he expected to gain by pursuing support after this hypothetical change in income. If one can barely support themself, how are they able to support their children? That's why the saying - you can't get blood from a stone. If there's no money, there's no money.
If anything, it's an argument for better social welfare, but that's for another forum.
It doesn't automatically make anyone a "bad guy", but it does make me wonder what the heck the father was hoping to achieve. And makes me wonder what the home atmosphere was like, with so many support/divorce cases going on in several directions with various parents. It must have been hard for the kids.