A friend of mine was sold 4 female guinea pigs. It turns out one of them was already pregnant. She is going to get another cage for when they are born as there wouldn't be room for them all but is it safe for one of the other females to go into the baby cage with mum and babies or is it best to keep them completely separate while they are weening?

I have never had problems with keeping another adult with a mother and babies, but it does depend on their temprements. What she could do is put the mum to be and one of the others in the new pen, to await the birth so she has company, then if after the babies are born there seems to be any problem she could seperate them straight away. That way the pregnant one will always have company and shouldn't become stressed.
I have 2 pregnant sows at the moment due any day. They are sisters and always get pregnant and have their babies within days of each other, but I also have an old spinster pig who often goes in with a pregnant sow to keep her company, she seems to enjoy playing auntie, and only gets a bit grumpy as the babies get bigger and are close to being weaned.
it may be a case of seeing how it goes.

My last litter which are nearly a year old littered in a cage of 5 sows. She had no problems and the babies seemed to find Mam and her milk with ease. As Clucks said some sows can become a bit grumpy!
Remember to seprate the boars at 3-5wks as they could become sexually active and make their sisters, mam and aunties pregnant.

Emma x

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