RE: Explaining to Children Why They Cannot Have a Dog
I actually don't really suggest a chihuahua for a home with young children. They can tend to be really nervous animals, and I imagine being around children could be nerve wracking for them. It's true that they can be trained to go on a pad, but they are a more difficult breed to train than people sometimes assume. A lot of them will pee when they get either excited or scared even if they are paper trained. There are a huge number of chihuahuas in the shelter system in California because everyone thought they were a cute animal to stick in your purse, but didn't consider that they might pee there.
I think they should talk to the children and explain why they aren't currently allowed to have a dog. I also think the idea of having the parent help the child walk a neighbor or friends dog is a good idea. I know that the shelter in San Francisco has a youth program so you could probably check there. I live in San Francisco and I regularly bring the kids to the SPCA and they are usually willing to let them pet a dog or two if they aren't too busy.