Oh yes, that's almost unbearably sad in so many places.
The bit that gets to me though, is the end, where the boy's learning to ride a bike, and calls Mr Tom 'Dad' for the first time. John Thaw's performance is just incredible in this, and he's sadly missed.
Other personal tear jerkers:
The Elephant Man
It's A Wonderful Life
Venus - a wonderful performance from Peter O'Toole