How would you handle this?

LO is supposed to be a flower girl in a wedding next Saturday. Rehearsal is that day at noon. Also known as nap time. Most wedding rehearsals I've known to last 1-2 hours though since it is the same day, I imagine they are going to be efficient.

Then she needs to be back at the venue and ready for the wedding by 5pm at the latest. I'd like to shoot for earlier because we always run late and she can be shy so it will help her settle in to not be rushed around. The wedding starts at 6pm.

The wedding venue is about 30 minutes away from home. LO falls asleep in the car all the time so I am wondering if we try to do two car naps that day - one on the way and one between the rehearsal and the wedding? More sleep is probably better than less sleep, but she can also get out of sorts when her regular schedule is off, so it is a risk.

I worry that if she naps too long before the rehearsal, she may not nap again after and being behaved for the wedding is probably more important.... BUT if she is tired & cranky at the rehearsal that may create a negative association and then it's probably not going to happen at the ceremony.

Also, I need to think of ways to make her feel comfortable and incentivize her to walk down the aisle and preferably not scream. I am trying to think of, like, an amazing candy/treat that is easy for her to eat with just 6 teeth so we can "train" her to come down the aisle. I am almost thinking we should start practicing in the backyard. I just asked the bride what song will be playing, haha.

Help!