Unbiological Dad--Driving us crazy

I want to be clear that I'm not an expert in anything, and I've muddled through with my own kids. I also haven't fostered, so I can't speak to those kinds of relationships. That said...You said you want him to be involved since he had been (clearly not anymore?) taking care of them, and it sounds kind of like you feel that he's owed that. I'd try to make sure that first you know what's best for the kids. Your responsibility is to them, not to him. If there's a version of that that also includes that feeling of "owing him", then cool. But if there's no good from it, it doesn't seem like a great thing to continue.I also have no clue how responsible he is, but perhaps you could also say "hey, here's the problem with these calls: A, B, C. And here are the ground rules: no pity party." If he can't figure it out then remind him. If he still can't figure it out, I'd stop the calls.Another possibility would be to shake up the schedule a bit. Maybe limit once or twice a week. You could do that and also have ground rules.Recently we adopted an 18yo daughter. There were stressful calls with her bioparents as well. She made it clear that when the adoption was final, she didn't want communication with them. I can tell she still would like their approval, but it was a good decision and something that she needs right now. Eventually maybe that'll change, but for now no communication is what she needs.I started out by trying to smooth things over and take less drastic measures. I'm glad that I tried, because I'm confident that her course is the correct one, but sometimes drastic measures have to happen.Of course, in our case she's an adult and can do whatever she wants. And it's easier to understand how she feels and what she needs than a small child, but it's still complicated.