I'll take ANY pitbull over most chihuahuas/small dogs.
mom adopted this small 15 lbs turd with fur that strikes at anything that he doesn't like (except mom of course), little dog syndrome is real.
Interesting, I took care of (late in its life) a very frustrating 17lb dog that was friendly and when you pet him, he would turn and draw blood from you with a serious bite. After working with the dog it became clear he was never socialized correctly. After period of time, he became very gentle and affectionate. I also had a 9lb dog that had a miserable life as a puppy mill breeder and she too needed work to help gain confidence. It seems your 15lb biter had issues that someone simply failed to address properly. BTW, I have dogs in the 80lb range so I am not merely advocating for small dogs but pointing out your biter dog could have been addressed most likely but wasn't and that is not little dog syndrome when the dog prefers one person and attacks others. Indeed, no one knew how to deal with your mom's dog.
[doublepost=1516070480][/doublepost]Anyone who has seen Our Gang comedies/Little Rascals will remember Petey their dog who was a "Pit Bull" breed. These breeds used to be called family dogs and it appears there are many things going on with these Pit Bull breeds that should be addressed (in my opinion).
All of these breeds should be neutered/spayed/sterilized in the USA unless a proper breeder who takes the time to do both physical and behavioral research on the parent lines. These breeders should be licensed and in turn, those that wish to have some of the more "dangerous" breeds of dogs should be required to take a knowledge test, have a background check of ability to properly care for the dogs. Laws should be stronger where animal abuse is concerned and especially for dog such as these that have a very different behavioral response from other dogs leading into fight behavior.
In short, these breeds need to be "reworked" to get them back into their original spec size/form and behavior. After years of being bred for aggressiveness and a bit "broken," it is time to fix them so there are future issues as only rarities. Every Pit Bull breed individual dogs I have met were truly outstanding loving pets. However, I have also seen from afar, owners who keep them as "macho" extensions of their small peckers be more than cruel to their dogs. These are the types of owners that make the dogs react badly after an amount of time or fully withdraw.
Perhaps less drama and more constructive action is needed at this time to fix these breeds, get rid of bad owners and abuse venues (dog fights) etc.
As for me - I am more involved with the Spitz breeds which include everything from the Pomeranian up to the Malamute.