Hello & welcome to
GPC.
If your pigs are purchased from a petstore, please please verify them with a vet just to be sure of the sex.
GPs multiply like crazy so for a breeding pair, you can end up with 50 - 100 pigs within a year (the dad will breed with his daughter even when the mom is pregnant etc..) easily!
Verifying with a vet also gets your
GP's info pre-booked into the vet's systems so they can get emergency care easier than having to wait & fill out forms when you first visit (saves paperwork time). When they are there, you can have the vet do a check-up for any hidden illments like URI or treat them for mites & such.
P.S. look for a
cavy savy vet.
Good luck with your boys.