What kind of logic is this family going by... unless the ex-husband expressed explicitly that he didn't want the child, why wouldn't you allow him to be in the child's life and help provide for the child?
Okay so, she hides a kid from him, brings it up nonchalantly while drunk (being taken care of by said kid), she gets angry at him for caring about the kids well being.
And this guy's just like? Yh cool that's fine I guess. 💀💀