Thompson watches Diego like a prized pupil. Things Diego has done for months (and in some cases years) Thompson won't try until I'm guessing he feels it is totally safe to do.
Last night was a good example of this. Diego loves to crawl in bed next to me and lie face to face while pawing at my chest and neck. Thompson has never ever done this until last night. Usually Thompson is content lying at the end of the bed or if he needs attention he will wait until I'm lying on my back and then hop up on my chest and sit until I rub his face.
Last night he lay down next to me and with his one front paw put it right at the top of my chest. Although he was purring I could tell he was a little antsy about this "new" behavior and gave up his spot when Diego arrived to take his usual spot.