My young son's partner is very thoughtful when it comes to cards usually, I do a lot for their children and always get thank you cards written by her from the children, so it is unusual.
In previous threads I have mentioned that my two sons don't speak after a fall out regarding this DiL and as I spent time with my other son and his family at the weekend I have wondered if that might be something to do with it. Both sons think I do more for the other, which most definately isn't the case, but nevertheless it creates difficulties at times like this, as I can't see both families together. Family celebrations are always fraught. I was asked by my elder son to go out with his family so I accepted.
I have to tread very carefully with the partner of my younger son, always walking on eggshells in case she takes things the wrong way, but I don't think anything has been said that she might be offended about recently. In fact everything was fine the last time I saw them (I had had my GD to stay for the weekend and they came to collect her).
I will choose very carefully the time to say something to my son, I won't ring him up and make a fuss, maybe wait until he rings me or when I see him, but that won't be for some weeks.
I hope I'm just over reacting and being too sensitive!