Am i financially responsible for my moms phone if my son possibly ruined it?

Question

My son is Autistic and does not know any better and dumped shampoo onto my moms phone. Our apartment has two bedrooms in the back half with an access door. When its shut the baby lock keeps him from gaining access to the back bedrooms, one of which is my moms. I shut the door to make dinner, so that he would not have access to her room or mine while i cooked.  She came out of the back and opened the door giving him access to her room. She didnt tell me she opened the door nor did i see her leave it open so I did not know it was open. She knows that he is Autistic and regularly will dump stuff out and also tries to keep the door shut usually. This time she did not. Now i am being threatened with getting a lawyer and making me pay for it. Am i responsible because he is my son or is she at fault for leaving access to a child she knows can cause damage without informing me of the change in security to her belongings?

Brent T. Geers · Answer

This is a matter of what's more important to you: do you want to be right, or do you want a relationship? And I suppose the same question could be posed to your mother. 
 
I don't know enough facts to say whether your mom would win a lawsuit. You, though, would probably come out further ahead by offering to pay for a new phone; $800 or whatever is a silly reason to severe a family relationship. I do not know if your mom lives with you or you live with her, but maybe it's time to change living arrangements.

Q: Am i financially responsible for my moms phone if my son possibly ruined it?