Something like that happened to me too. I want to volunteer at some shelters during summer vacation, so I always try to find shelters on the Internet where I could work at. I emailed some, and all of them would reply very nicely and give me a long reply, explaining how they're happy how I'm so young and I love animals, and they like how I would want to volunteer and said maybe when I get older I'll work there. and they also told me a lot of things, like even if I'm only 13, I could volunteer too, but just not directly with animals. So all the shelters tell me that, and are really nice to me. One even said that even though I'm too young, I could foster animals, and told me all this information.

But only one got me kind of mad. I emailed them a long email, and told them that I am only 13, and if I could volunteer or anything. Their reply was just one sentence: You're too young, get back to us when you're at least 16.
I don't know how you guys would react to that, but I got kind of upset. Some other shelters said that I can't volunteer because I'm too young, but their reply was longer and much nicer.