No pet -pure or mixed breed- comes w/a guarantee. Even dogs from a reputable breeder can develop behavioral problems once they are placed w/their new owners, most often b/c of owners not understanding how to properly socialize dogs. The good news is that most pets can be rehabilitated by loving and patient owners. And really all dogs -behavior issues or not- require owners that carve out time every day to work w/them on obedience and exercise; if a dog is not mentally and physically exercised each day, they will likely become neurotic due to boredom. This is not to suggest your family take on a challenging pet they don't believe they are prepared for but more to point out that all pets need an investment of time and energy. That said, I do think it is smart to consider specific breeds/breed traits that match up w/your family's lifestyle and temperament, so research on that end will likely help find a pet that's good for your family. As boxermom pointed out, there are breed-specific rescue groups out there, and not being set on a puppy will increase the likelihood of finding a great pet soon. I don't object to reputable breeders, but I also suggest that people first consider a rescue since there are so many loving pets waiting for homes. Good luck!