Starting a colony with already pregnant females.

We have a shortage of mice in my area due to the issues with RodentPro, so I've decided to start breeding mice again. I was able to acquire some females from one of the local pet shops, and I picked two that looked prego, just to get babies more quickly.

My question is about setting up a 1:2 colony with a male from a different shop. I never had this problem when I bred before, so I don't know the answer! Will the male be ok with the babies that are soon to come, or are they like new lions taking over a pride and will kill any babies that they think aren't their own, even if they are born after he's introduced?

I only got these kids today, and set them up in a 20 gallon long, and everyone is getting along. He tried to mate with both of them, but it only took a couple tries before he figured out they would have none of that and quit trying.

i would take the male out. when i bred mice i always separated the males. the issue would probably be the females eating the babies. rats on the other hand my female rat had a litter while the male was still in the tub with her and they were getting along just fine before i separated them and no babies were eaten by the momma.