How does your grandson handle late night emh? I think Dd is close in age to him, but we've never ventured to evening emh with her. If we do it, she's back at the hotel with grandparents. Evening emh is one of our favorite times, so the idea of being able to include her in that is definitely appealing.
He's 3 1/2 and was a trooper! We went to 2 emh's that ran until 2am. The first one, on a Saturday, our first day at WDW, we arrived at WDW around 10am, had our room by noon and we spent the rest of the day at the resort. We went to the MK around 6pm and we all lasted until just after midnight. No problems at all. Some of my family went to the last day of SWW the next day and because I'm not a fan, I stayed at the resort with him that morning and went to MK around 10am just to use FP's for meet and greets and then lunch. After that it was a pool day at the resort until the fireworks at HS that night- so after that emh, he got a light day the next day.
The 2nd one was our last night at WDW. We were all a little tired from being there all week. We all slept in a little and relaxed at the resort most of the day, then went to Epcot around 4. We had used our 3 FP+'s, had a long dinner and watched Illuminations. We headed back over to the MK just in time for emh's to begin. I lasted until close to 1am- but he was still going strong- no meltdowns, no signs of tired. I took him by boat back to the resort- he fell asleep in his stroller on the way back and never budged when I put him to bed. And since we were leaving the next day, there was no early morning the next day.
So, it was undoubtedly tiring for him, especially that second one, but he handled it very well. We basically took it fairly easy the day of an EMH and had a light morning at least the day after. I think that was the key to making it work. That said, I had volunteered to be the one to take him back the minute we had any problems with him- we just didn't. I gave up before he did!
I think if we had tried to do an emh evening, then get him out of bed to try and rope drop the next day- or even wake him up before he naturally woke up, we would've had a very cranky boy. He didn't sleep terribly late the mornings after, but later than his normal 6-7am waking time.