[header] How to care for baby guinea pigs [title] Measure the size of your guinea pig cage. [step] Pups will reach adult size very quickly, so it is recommended to have your pups in a cage that is an adequate size for an adult guinea pig. The cage should be at least 7.5 square feet. 
If you purchased pups from the pet store, make sure that the cage is large enough before you leave the store. [substeps] Even though the cage may seem a bit big for your pups, they will appreciate the extra space they will have to run and explore their environment.