May be he meant the puppy's number?!

Speaking as someone named Olivia, WHO CALLS A DOG 'OLIVIA'?! THAT IS NOT A DOG NAME IT'S A HUMAN NAME. MERHH.

27 maybe he's a milf hunter with low standards ever thought of that?

It just sounds like OP's mom didn't want the name for the grandchild so she took it in the hopes that OP would choose another name.

OP doesn't actually specify whether or not the mom knew about the desire to name the baby Olivia. What if she didn't know, and everyone is just assuming she's a wretched bitch?

I would go with Olivia anyway, it's a beautiful name. If your mom didn't know the name yet, tell her, and it'll be a funny story to tell. If she did then I would point out her behaviour and let her know you're angry with her. Maybe she is just trying to help in her own twisted way. :/

Am I the only one that thinks it might have been her mom's attempt at a sweet gesture, as opposed to being a bitch? I think its adorable.

Talk to your mother about how you were planning to name your child Olivia.

Many people here are saying the mom is a bitch. Isn't it possible Mom didn't know? I never told anyone what I was naming my children before they were born. Also, many dogs have human names. There isn't a rule on what you name them. Olivia is way over used now anyway. It's like Cathy or Karen was back in my day.

Your mom did it on purpose. My mom figured out a way to kill a baby name she didn't like too. Moms are sneaky that way.