As it's my 21st this year too

I would want something I could keep to remind me of that day...
Only my warped mind may be adding but... why don't you ask what time she was born/ weight/date of birth etc etc and get it engraved on a cup/glass or a charm braclet?? with added names of friends now

After all on your 21st we all go out with our friends and party/dance and have far too much to drink to recall the day, maybe one too many but something to keep on the shelf collecting dust

to remind you of that night.. when at 25/6/7/8 and 65

loads of kids

... she can look back on that drunken night and smile
I only say that because I smile every time I polish my past treasures