Breeding siblings?

Question
I have a Guinea Pig, Male born the 4th of July. He Was giving to us at 4 weeks old. We decided we wanted to expand our family and get him a friend so he isn't lonely. The same person who gave us him just had another baby and offered the baby to us once winged. We don't know the sex of the baby, we really didn't care. Baby would be nice to experience once, but our main concern was to get our spoiled piggie a friend. I'm pretty sure the baby will be his sibling. Maybe only 1/2 sibling. If the baby is female and they mate will everything be ok? Should we keep them apart if the baby is a sow? If not will both males get along?

Answer
Hello April,
personally I wouldn't try and breed the guinea pigs. Guinea pigs have difficult births because the babies are born to basically look like mini versions of their mom. They are fully furred, ready to run, play and eat. They are large and it can be difficult for the mom to give birth. I do know many breeders stop breeding because of the fact that they can lose the sow or the pups during or after birth.
It doesn't matter if the other one is a boy though they will still get along as long as you introduce them in neutral territory and give them a chance to get to know each other.