To be on a safer side, she shouldn't have had any babies until at least 3 months old. This would have given her time to finish growing and maturing. Anyhow, wait till the baby is eating on its own and not nursing so much...about 2 1/2 wks old. This way, if the mother decides not to nurse the baby anymore, it will have more of a chance to survive. I usually separate my babies from the mother at about 3 wks, she starts to attack them at this age if they try to nurse. It's happened to 2 different batches of babies already.