Nursemaid mouse has her own litter

Question
i found 9 baby orphan mice in a bag of mulch and want to a pet shop and bought a "milk mouse" since the guy at the pet shop guaranteed that another mom would take over her babies while know she is pregnant and you can see the babies moving in her stomach will she stop nursing my wild mice babies once she has her own?
thank you for any help and your time

Answer
Dear Sarah,

The nursemaid mouse thinks those babies are her own.  Unless she has too many pups to nurse, she will nurse them all.  If there are too many, chances are she will let some of her own die-- only because they are smaller and have less a chance of getting milk.  

Have fun with the babies!  But don't let them mate with mom mouse.  First generation half breeds are notoriously crazy.

squeaks,

Natasha