I am feeling really hurt about this but suspect I might be being unreasonable.
Both brothers are a lot older than me and their DC are 10-25 years old. In 25 years I have only once forgotten one of their birthdays - years ago when my niece was 13. My mother rang and told me that DB1 was extremely upset, so I quickly sent a nice gift and a "belated birthday" card apologising for being a forgetful idiot. I was eventually forgiven but it was quite a big deal at the time.
Last week my PFB turned one. Neither DB1 nor DB2 sent even a card. I feel really sad for DS. Especially since all of DH's family, down to his great aunties and even some of his parents' friends, sent cards and gifts. I know some families just don't do birthdays, but that isn't the case with mine.
I wish I could say something to them, but what could I say? I don't want to make a big family drama (my family has too many of those already). AIBU even to be bothering about this?