Oh man. He is soooooo beautiful. You did good mom ! I admire your passion and determination to have him on your terms. You did it and he looks beyond happy.
Baby kittens are the best after baby humans. You may be able to contact some no kill cat organization/rescues and get help with litter and food since your little girl is a rescue. Especially since she’s having babies. They can also help with placement so you don’t end up with 6 cats in a few months.