Growing up my parents never mentioned their wedding, there were no photos of it or anything like that. They also never celebrated their anniversary or mentioned the date.
My siblings and I are now adults, and recently my parents got upset because apparently it was a 'round number'/'big' anniversary and none of us did or said anything. Because none of us had a clue.
I suppose I could have asked them their anniversary at some point during the years but it never occurred to me to do so, they never so much as bought each other a card that we knew of, so I guess we just assumed that it wasn't a big deal to them.
We've always made a fuss of them for birthdays/mothers and fathers day etc, so I hope they don't feel generally neglected.
They didn't mention/do anything for my wedding anniversaries, and nor would I have expected them to (the only person who I would expect to remember is DH!).
Aibu for thinking if you want family to celebrate your anniversary you should mention the date to them? Or should adult children be expected to find out your anniversary even if you don't tell them?