Is your DD able to check her blood sugar and know what a low/high number is?
Around 8 is when I started feeling OK with dropping her off at a party. She carries a cell phone with her and has a CGM, so that gives me much more peace of mind. If it is at her friend's house, I speak to the child's parent briefly before I leave and let them know DD has Diabetes and that she can manage it pretty much on her own, and try to find out what foods will be served. Then, before DD eats she checks her BG and calls me and we try to guess the carbs and she boluses.
For parties in a public place, I still hang around if possible. For instance, she recently went to a party at a supermarket with a Cooking School. I dropped her off and then did some food shopping while the kids were making/cooking the food, but stopped back when they started to eat to help her count carbs and bolus.
I would do whatever you and your DD are comfortable with, even if it means you stick around at the party until you're both ready to drop off.
Linda, mom to:
DD, 11, dx'd 2008
Animas Ping with Apidra 4/2009-8/2013
Dexcom 7+ 4/2009-11/2012
now using T:Slim with Novolog and Dexcom G4
DD, 8, non-D