Talk to your parents. I'm assuming they already know your grandmother is allergic to dogs and that you have two of them. They probably worked out some kind of solution with her.
Get your granmother to stay so where else - joke.
See if one of your friends or other family member could have the dogs. Not far you have to chosse between the two.
Try to convince you parents to let your dogs stay in some other room in your house, build them a dog house in the yard, ask your friends to keep one or both of them at their place....... I got nothing (if your dogs are hypoallergenic dogs then your granmom has no need to worry)
