who has father like this

A son says to his father: 'Dad, would you be willingly to run a marathon with me?'The father, despite his age and a heart disease, says 'YES'.And they run that marathon, together.The son asks: 'Dad, can you run another marathon with me?' Again father says 'YES'.They run another marathon, together.One day the son asks his father: 'Dad, would please do the Iron Man with me?'Now just in case you wouldn't know, 'The Iron Man' is the toughest triatlon in existence; 4km swimming, then 180 km by bike, and finaly another 42 km running, in one stroke.Again father says 'YES'Maybe this doesn't 'touch' you yet by heart ... until you see this movie (put on sound!):http://www.youtube.com/watch?v=VJMbk9dtpdY