Is she going to be half days? I know that other people I know that have to do half day pick ups will play at a playground beforehand, then pick the child up, or find a play group or early years centre near the school, and pick the child up on the way home, kinda thing. You don't have to cut nap short, just try and find a way to modify the schedule.

If the mom's cool with the 8th grader doing pick up and drop off, then it's a non issue. Hope it goes your way!