Guinea Pig is Rejecting One of Babies

That's right, a guinea pig baby can eat real food right away, although they do nurse for a while as well. You can also offer it a tiny bit of bread soaked in milk. You should also know that a female guinea pig can get pregnant again within a day of giving birth. So if the male is around her, you'll be doing this again! The second time I went through this I found a vet who would neuter the male. On the upside, baby guinea pigs are so adorable being born with all their fur and their eyes open.

I had GP's as pets years ago. I have no experience with a mother rejecting a baby, but if I recall correctly GP's can start eating regular food right away, so I'd just remove it from the "cage" and put it in a separate "cage". You might put some of the other babies in with it now and then so it won't be socially deprived, pet it, etc.