Milton was a different bird the first two years he was with us...quiet, unassuming, and very fearful of anything new in his world...definitely un-'toolike behavior.
When his heart had healed, he made the "leap of faith", as I always call it, to trust again. That's when Milty "became" the Milty we see today...happy and full of life.
As for what happens when we visit, it is bittersweet for us to see...the residents don't know Milty's history, so they just think he's very friendly...it gladdens the hearts of all...Milton's...the residents... and us...
I guess it's similar to humans losing the loves of their lives after many years of being together. I am so very glad Milty made that leap of faith!