For context, my DSis lives 10 minutes from my mum. She uses my mum as a third parent and my mum is expected to drop everything at a moment's notice.
DSis refuses to host mum at Christmas and will only see her in laws. The in-laws have a great relationship with mum and always ask for her to be invited.
DH and I always host mum. She's due later. This year she booked her Christmas invite in JUNE because she hates being alone.
I've just phoned her and she's really upset. Not even a text from my sister.
I've raised this before in previous years with my sister and the response I get is that mum is not required at Christmas!!
Am I being unreasonable to be really upset about this?
I'm not going to bother raising it with DSis again.