My daughter had a small horse named Tiny Horse. He was always old. When she died in 2002 some farm friends in Kansas took Tiny in and he lived a life of luxury until he died in 2012. Vet there said he was the oldest horse he had ever seen and the vet was almost 70.
Great that you took Moon Ace in. Sure you have some wonderful memories. Not sure why people just never tend to their own business.
Moon Ace was taller and faster than the other horses we had. He had a very good disposition not high strung like you might expect from an animal bred to go fast. But you didn't want to jump on him bareback especially if he was pointed toward the barn. It was a good way to get a black eye. My teachers used to think I was an abused kid because of all the spills I took. I still have dents in my scull from those days.
Moon Ace put up with me and my brother and sisters and later my nieces and nephews. Everyone loved him even when he looked like a saggy old sack of horse flesh. By the time he and Morningstar left this world for horsey heaven I think they were both half blind. Morningstar still had a few teeth left. It is probably silly but I like to think that my old friends are running around green pastures together, restored to their former glory. They were both beautiful animals in their youth.