Two - three weeks. Any older than that and males could make their mother and sisters pregnant. If you are * sure * they are all females, then it's not a problem, they can stay together. Guinea pig babies are technically "precocious" - like miniature adults, with a full coat of hair, all their teeth, etc, and they can eat adult food as well as suckle from their mothers almost immediately. Check the guinea lynx website for details on guinea pig care, including how to tell whether they are male or female. If in doubt, though, separate the, just to be on the safe side because back-to-back pregnancies would be bad for the mother's health.
4 weeks. Pigs are unique in that they can eat adult food right after birth, but they still need all the fat and nutrition from mom's milk. 4 weeks is perfect and you should be able to sex them by then.
Three or four weeks at the latest. At around 21 days old they can become sexually mature so no longer than four weeks. And you only have to separate the boys, girls can stay with mom.
do it like a 2 weeks after, not much later, they get rowdy really young
