I mailed a similarly thankful note to the nurse who accompanied the kids on the trip. My daughter was in touch with her regularly via text, and they always knew where the other was. The nurse carried a little bag (within her giant 'nurse bag') with glucagon, glucose gel, and a spare meter set. Her assistance was never needed.
These notes reflected my acute awareness that my child was fortunate to have such a fun and positive trip. There are other kids who are allowed to have these kinds of experiences but with much less quality support. And there are kids who are told (illegally but indisputably) that they can't participate at all. For three days Dexcom Share was my most-used app. The texts about the frosted flakes for breakfast and the bus full of rice crispy treats were cringe-worthy. But mostly, I'm thankful.