Should I be more concerned about my dog being around my dad's dogs?

My dad has a 13 y o german shepherd (Chief), a 13 y o lab (Remy) and an 8 month old yorkie (Teddy). My dog is a 7.4 lb Pom/chi and her and Teddy are best friends, so I take her with me whenever I go, usually from early Saturday to late Sunday and maybe another day or two. The big dogs have been ok with her so far (her and Teddy even gang up on them and steal their toys and treats) , but Chief is going deaf and Remy is in increasing pain from hip dysplasia, and is being tested currently for kidney failure, which they think he has. I know dogs get more irritable from pain and illness, and jumpier when they go deaf, and one snap from them could be pretty catastrophic. I always supervise closely the entire time, but should I start keeping her totally away from them?