When you wrote this part you forgot the other angle that they come with regarding reducing the time 'at grandma's' when your article speaks this: "“Um, what?!? I don’t understand.” That was her way of saying, Oh, no, you didn’t! You are not going to rob me of a night with my grandchildren!". If it is similar to me, that extra day that she already 'allowed graciously' had a debt marker on it an you're removing that from her bookie log of how your owe her! Or maybe your mom operates a bit differently:).