I don't think they're patting her on the back.

They're acknowledging that the ex is a major dick who overstepped his bounds and tried to take advantage of her.

Which he did. Clearly.

The more you think about it, the worse it actually gets because you keep think of all the potential fallout that she could have had to deal with, like her own lost wages, maybe losing her job because she too is out of time off to take to take care of his kid, not having that time later when she needed it, CPS investigation if the school reported one or both of them, being drug into family court, emotional stress and duress from being coerced into caring for the kid if she knows she can't handle it. There's no end to the ways this could have spiraled very badly for her.

Plus, it's just rude.

They're acknowledging that. It's got nothing to do with the kid or blaming the kid for what the dad did or any of that.

The guy overstepped.