We got a Save the Date and a college graduation party invite. Both from DH's niece and nephew who lost their mom in December. They should be happy, but the grad party came from FIL and sMIL. I know sMIL wrote them all out and it had to really be hard- knowing her granddaughter is missing her mom and knowing that MIL's daughter should be filling them out.
It's got to be hard not having your mom on your wedding day too. I know FIL is hosting the rehearsal dinner and I'm guessing there is more they are involved with.
I hate this for these kids and for my ILs.