My dog is older than me

Recently the old lady next door had to go into a nursing home due to ill health. Because her dog has always got on well with my cat, and because she knows that I’m fond of the dog,she asked me if I wanted to have it so that she knows it’s not going to strangers. I agreed to have it. The dog is a 15 year old highland terrier. I’m only 14 so I actually have a dog that’s older than me. I’ve promised the old lady that I will visit her in the nursing home and take her photos of the dog. Also, I will find out if the nursing home allows visitors to bring dogs with them when they visit and, if they do, I will also take the dog to see her.