Hi boxedmoon. How lovely, baby gerbils!
I`ve only just seen your post as I havn`t been on the forum very often due to illness and nobody had replied so thought I might answer with my thoughts. I used to keep gerbils and still love them even though I havn`t had any since.
Now, your female mum will appreciate one or two of her daughters staying with her. I say two because if mum was to pass on, you would then have company for any younger female that was left alone if you keep two female babies. The other two could be rehomed as a pair, so a win, win situation. But female gerbils are more likely to fall out.
The boys are more likely to stay together as males are a bit more laid back anyway, although I had four male brothers and two de-clanned as adults and had to be split away from the remaining two. So it doesn`t always pay to keep too many together. Pairs are more likely to get on rather than trios or groups.
You have dad and three sons, so your choice is to keep one baby boy with dad or two and rehome the single male, but that`s not ideal really as you want to try and keep them at least in pairs where possible. So dad with one baby son and pair the other two off.
Any thoughts? have you kept gerbils before or are you new to keeping them? They are great fun and so funny. x