No, unfortunately a seller has no obligation to disclose conditions (like a pack of dogs) that exist at any property other than the one being sold, or the behavior of neighbors, even family. You have no recourse against the seller. However, this may be a violation of town health or noise ordinances: you should contact your town's health and police departments about what the local laws (ordinances are local laws) are about noise at 5am (as well as about permitted volumes) and also about whether there are any health-related concerns (like dog waste) which may also be a legal violation. If any ordinances are violated, she can be fined or ticketed until she corrects the situation--even if that means muzzling the dogs or even getting rid of some.