Am I the Asshole for expecting my brother-in-law to pay for my Seadoo after he let my nephew wreck it.

I just had my family out to the lake for Memorial Day. I work remotely from there so it is not just a vacation home, it is my home.

I am single and I like to buy myself toys. I also like to entertain. I own two Spark trixx 800 cc Seadoos.

They are a lot of fun but also really powerful.

My sister and her family came up for the weekend.

We had a good time and I had a blast towing the kids around on a tube.

The problem came when one of my nephews wanted to drive the machine. I said no because, while I may call it a toy, it is not a toy.

When I was in the house my brother-in-law let my nephew drive. But they skipped a step because he is an idiot. He forgot to attach the tether clip to the life jacket.

The kid lost control and fell off. Normally the tether is a dead man's switch and turns off the machine if the rider falls off.

So then the Seadoo took off for a bit and then started making slow circles until it ran into a dock.

A bunch of the plastic on the top broke and some just got badly scratched.

They came and told me and I told him he had to pay for fixing my machine. He is mad because it was an accident. I said he took it and gave it to someone who didn't have permission or experience and he is responsible.

My sister and I talked and she paid me for the parts I will need to fix.

My brother-in-law is pissed because it came out of their "fun" budget and now he has to save up again for their vacation.

AITA

EDIT.

My nephew wasn't hurt. Just scared because of falling off, almost getting run over by it, and having to swim to shore.