I like to have a conversation with Mother dearest!! Please op, don't sell or share the necklace. Take a picture, get a safe...what ever you can do to protect it, but it not if it's when she will try and steal it!
NO!! She shouldn't have to put her feelings and emotions aside to please Sally! Sally chose to have a baby...OP didn't! If your allergic to peanuts and somebody want to give you a peanut butter cake....you gonna say thanks! No, your gonna decline? Same thing! Sally and everyone who things she should just "suck it up" are jerks!