You know mice are fickle sometimes it is the case and sometimes the don't care. To be limit as much risk as possible I would get all the females and 1 male at the same time, make sure they are the same size and if possible get them from the same place.Originally Posted by justincturner
When I got mine they kept the males and females together (primarily a feeder store) so mine were used to each other from the get go.
Good Luck.