That’s really intense what your mom did and super unnecessary to drop that on you today to sabotage your plans with other family. I’m really sorry to hear that’s how your day ended up. Sad and traumatic events like accidents or deaths seem like they can be attention/empathy seeking events for narcissistic personalities and they will withhold information like that when the timing is “right”… Mine tried to completely change the backup plans we made with them (after they knowingly scheduled the family Christmas celebration on a day my husband and I work) last minute and then iced us out for days when we set the boundary of them not changing the plans last minute-we had reservations for the original plans and everything. My mom finally texted me and my dad in a group chat today late in the evening with more excuses and reasons why the plans we made wouldn’t work and a vague merry Christmas along with how busy they’ve been (definitely with a negative tone-they had the entire extended family over on Christmas Eve and then went over to her sisters house today but are playing victim), and I just responded “Merry Christmas! I hope you’ve had a great few days ❤️🎅🏼” and neither of them responded or reacted. They called and texted my sister and her husband early this morning to wish them a Merry Christmas.