One of my favorite character interaction was on our first family trip in 2009.
We had been touring during Easter week and I was wearing down. We went to Camp Minnie-Mickey to see the head cheese but also decided to stop at the other trails because there was no.line.period!
I decided to keep DD6 months in the stroller and let DH and DS2.5 go up to see Goofy. When the boys were done with Goof, he left his spot and walked over to DD and patted her head and gave me a hug. I thought it was great that he didn't want anyone to be left out.
On the same trip, we went to Ohana for a super early breakfast. Mickey came up to DD and stuck his nose so close! She just stared at him and grabbed his nose. He just let her do it for a minute or so, gave our cousin (who was holding her) a squeeze, and set off to the next table.
This past December, I had two REALLY good interactions. The first with Alice in MK. I ALWAYS take a pen that is at least 12" + long. Alice asked if I poured some of the "drink me" potion on it. Of course I told her yes! We went back and forth for a few minutes and I
just about got her tripped up on her own story. I told her that I used my pen to test the liquid because if I drank it and became a mile high, I'd be kicked out of the park!
On the same trip, we stopped by
MVMCP. I needed to get Cinderella's autograph to mail to a friend's daughter back home. So I stood in the Tremaine's line. Just to find out that they weren't going to sign autographs.

My travel party didn't want to wait in line, but I wasn't going to waste the time I had spent. I greeted the family solo and Prince Charming and Anastasia went on and on about my pins. Charming got tripped up on a Sword in the Stone pin (couldn't remember Mim's name). Anastasia mimicked the Wilderness Explorer's chant and Drizella, feeling left out, completely photo bombed my shot with Charming.
I didn't see it until I got home, but I swear, it's one of my most favorite shots from the trip!
Look deep in the background... Drizella is choking Anastasia fighting for attention.