X2 on the prolapse. It can happen to any animal during labor. If they are having a hard time pushing a baby out, they end up pushing too hard for too long and it happens. Something like that would require a vet visit to fix. I'm sorry your little momma mouse didn't make it. Good luck fostering! Hopefully some of your other momma mice are willing to help out.
i already have them with the mouse that will foster them i will be checking to see how she is doing.
1.0 albino
0.1 black pastel 66% het. albino
1.0 cinny