When I read this, it reminded me of some of the things that I try to do daily. I like to say that I never have to worry about a second childhood, since I have no intention of getting out of the first one.
A good example is one night last week my wife was watching tv in the kitchen. A 2 year 4 month old girl came crawling in one door and out the other. Right behind her was a 61 year old great grandfather, on his hands and knees, playing follow-the-leader. Wife just shook her head. That child spoils me unmercifully, but keeps me young.