At the moment it is watching my lad grow up into a young man, polite and with empathy. Celebrating all the good things he is doing at school and on the football pitch. Seeing his face and reaction when he finds out a piece of information that he thinks is really cool.
Previously it was the reading of bedtime stories, I used to love that so much, reading out Dr Seuss, Harry Potter, Phantom Tollbooth etc.
He still insists on me piggy backing him up the stairs to bed every night, and wrapping him in a warm towel after a shower even though he is 12.