Krissim Klaw -I know I don't start threads often, but I've come here needing some help to try and persuade my Aunt to not irresponsibly breed her Chihuahua. I’ve tried talking to her a few times about it, but I know the best chance I have will be to show her outside sources via email.
It's nice to read that you want to stop your aunt, and provide her with as much anti- breeding info as possible. 
Krissim Klaw-For a little background info, her Chihuahua Luigi was a pet store Christmas present . Not sure he’ll ever be fully potty trained since they use pee pads and Luigi thinks all soft materials=pee pad, but overall their care is pretty good.
First, Luigi isn't even completely trained, he is still going potty in the house, and in my opinion, your aunt hasn't even fully trained her dog, let alone, getting ready to usher in a new pup. I won't get started about pet stores. A really good article about the errs of pet store dogs: http://hattrick-dals.home.att.net/10Reasons.html
Krissim Klaw -That being stated however they decided they want to get a friend for Luigi and have come to the conclusion that breeding him is the best way to go about it. First off, he isn’t even a year yet, and they plan to breed him when he is only about a year (when the female they chose goes into heat). When I asked about genetic testing, which she hasn’t done nor heard of, she admitted that they already know he has elbow problems.
Chihuahua's, like most other breeds, are prone to a slew of health issues, with heart, elbow's and eye's being at the top of the list. I have provided the link to the Chihuahua parent club's link about health testing. http://www.chihuahuaclubofamerica.com/health_testing.htm If anyone should know about the illnesses and diseases that effect Chihuahua's, they're the people to know.
Krissim Klaw -As if that weren’t enough, they just sent me the info on who the female want to breed him to. (along with asking me if I would be interested in one of the future puppies -__-) It is a female Chihuahua, no papers, who will be just a little over a year when they breed her to Luigi, and who has already, yes I sad already, had one litter with a poodle… As you can imagine I wanted to pull my hair out at the information of that poor female being forced to give birth when she is still just a pup herself and then being expected to do it so soon again.
Sadly, the people that your aunt is getting involved with, are not the most dog savvy of people, and are strictly breeding for the purpose of money. No dog should be bred before the age of two, and especially not before any health testing has been done. They already know that Luigi has health problems, and as another member stated, surgery is costly and may need to be done in both knees. If he is bred, this genetic trait may be passed on to one or all of the puppies, causing their future owners financial grief, and the dogs undo suffering.
http://www.chihuahuaclubofamerica.com/rescue.htm Again, the parent club had a great link to help your aunt search for Chihuahuas in her area that are up for adoption, so instead of adding to the unwanted population, she can save one.
http://www.adoptarescuepet.org/byb.htm This article is about the grim reality facing millions of unwanted dogs, which many are a direct result of backyard breeding, an act which your aunt would be committing.
http://www.breedingbetterdogs.com/author.html Dr. Carmen Battaglia is the author of several books about the subject of dog breeding, and about the influence of genetics in dogs. I highly recommend to anyone wanting to breed dogs, to read some of this mans literature. It's a shocking reality of the adversities that dog breeders have to face. There is no such thing as a perfect puppy, but it takes years of breed dedication and research, including health testing to have healthy dogs. They aren't born by miracles.
I hope some of this will help in your plight to your aunt. Good luck.
Ashley
In Memory of:
Cleo (1994-1999) & Dacota (1995-1999)
"Great dogs in every sense of the word".