How old was your LO the first time you took them to see fireworks?

This is the first year where LO's bedtime is late enough for fireworks. And the first year I don't think she will be scared by them! Butttt baby sister will only be 10m and I'm thinking she is probably too young. She gets pretty cranky if she's up past her bedtime so fireworks doesn't seem worth it to deal with that. Maybe I should just have DH take her and I stay home with the baby?
We have decent fireworks very nearby so they wouldn't really have to camp out too long beforehand.