They also seem to squeak a lot and then wee or poo… are they telling me something?
Welcome to the Forum and the wonderful world of Guinea Pigs! I always take any new piggy I have to the vet for a health check just so that the vet has a place to start from when the potential problems that come along.We can only ever advise, if you are worried about a potential health issue, that you switch from the routine weekly weight checks and instead weigh them daily so you can monitor hay intake more closely and see a vet to have any concern checked out.