I will continue to put up with it and will never stand in the way of my sister in law spending time with her niece. I know it means a lot to her. She also doesn't have any children of her own so I respect that she wants to spend a lot of time with her.

My daughter and your nephew are lucky kids to have family that cares so much about them. Which is why it's REALLY hard to for me complain about it... outloud anyway.