Around 25mins in when the family is watching "some Christmas movie" on TV, it's actually Krampus: The Reckoning (2015) which was also written by Robert Conway.
The second of three Krampus movies written by Robert Conway : Krampus The Reckoning (2015), Krampus Unleashed (2016), and Krampus Origins (2018). The movies are unrelated, although initially Origins was briefly marketed as a prequel to Unleashed.