putting baby mouse with father mouse

Question
Hi Natasha- Well here we go again. I was the lady with 2 orphaned mice that you helped so much last May. We were able to successfully raise them and about 20- 25 days go Luke and Leia presented us with one beautiful little mouse, but unfortunately Leia, who turned out to be a very good mother, tragically died a few days ago. We suspect she fell from her climbing  toy and managed to hit just wrong on her wooden chew bowl, because there was not a mark on her, but her neck appeared to be broken. Luke was standing guard over her when we found her.  So here we are again with a 6.5 gram orphan. Little Will is eating  some on his own; he likes to lick rice gruel and KMR off your fingers, likes plain yogurt,  mashed banana and even a tried a little smushed mouse kibble with  KMR, warm water and a tad of peanut butter mixed in. His favorite, like all kids, is mac and cheese.  He's also poo-ing on his own.  So I suspect he's going to do just fine. My question is, when is it safe to put him with his dad, Luke. He was in the cage since birth with Leia to protect him and there were no incidents, and he was in the cage alone all the first night after Leia died, out of the nest box and walking around, with no incidents, but now I have them separated. Little Will is in a smaller nesting cage inside the big cage. Luke appears  to be sad- he spends a lot of time just sitting on his wheel and  hasn't been back on the climbing toy at all. I think it might be good for them to be together, but want to make sure he won't hurt Little Will.  Any suggestions on how and when to put them together?  We have really grown to love our mice- they are so smart and make great pets. Thanks for your help.  

Answer
Dear Elizabeth,

I'm always glad to hear success stories about baby wild mice.  I'm very sorry, though, about Leia.  I think you can have the mice together now.  They will both be happier. It's sad for a little baby mouse not to have a big mouse friend.  Although I can't give you a 100% guarantee, grown mice usually respect baby mice.  And Luke must be very lonely after losing his sister.

I don't know what your climbing toy looks like, but if Leia fell off of it, it sounds like it's too dangerous to keep in the cage, especially because little mice can be pretty klutzy and also head blindly into dangerous situations, kind of like teenagers.  I always have to catch little mice who would fall off my arm in a way grown-up mice never do.  They just don't know their limits.  

Mice can be weaned at 21 days, so Will ought to be able to eat solids like seeds. He might want to nurse still till he's 4 weeks old.  

Best to Luke and Will!

squeaks,

Natasha