If you’re old enough to require a letter of recommendation, then guess what? You’re old enough to ask for it yourself.
Think about the difference in the letter I’m going to write. Who’s going to get my vote of confidence? The kid who called to tell me about the application for the school or program or the kid whose mom contacted me?
It’s annoying when your mom calls me. I’m accessible. If your mom has my number, you probably have it too.
When you need something, such as a letter of recommendation, ask for it in your own way.
Why are you allowing your mom to do something you could easily do yourself? Are you afraid? What exactly do you think might happen?