Putting two guinea pigs together

Question
Well right now I have one three year old guinea pig,Cuddles, who has a fairly big cage.  My friend got two other guinea pigs from the pet shop. She was told that they were both females, but then suprise, they had two babies. My question is that would I be able to get one of her babies at four weeks of age even if I already have a three year old one.  In addition how would I be able to get them used to each other?

thank you,
Cristie

Answer
Hi Cristie,

Sure, you can put a four week old in with a three year old.  You don't say if Cuddles is a female or male so I'm assuming female based on the name.  Females will usually not have any problems especially being introduced when the new piggie is only four weeks old.   Older males will usually accept young males as cage mates too. Males will sometimes fight when they get older, but not always.  You really don't have to do anything special to introduce them.  

...Only if there is a problem, try placing two cages (or separating one cage) so that there is only wire between them for a few weeks.  They may get used to each other and get along.

One big thing is that you want to be absolutely sure the new piggie is the same sex as the one you have.  A sow will be in serious danger is she is bred for the first time at age three.

Annie