Every year in the last 4 years we have eaten Thanksgiving at my FMIL house mainly because she always has lots of guests and just invites out small family to join. This year our whole extended family is coming for Thanksgiving so we invited her and my future brother in law to eat with us this year since she is not having any extra people. She declines and feels that it is tradition to always have a thanksgiving at her house. Well i hope she knows that i am not doing 2 thanksgivings this year and i would like to spend the day with my extended family whom i never get to see.