The time certainly does fly by when you're parenting, doesn't it @stevenwood?! Mine are now 20 and 23, two boys; I seemed to blink, and it was all over. It seems that some of the days were terribly long haha, but the years just flew.
How is it that we never age? :)
You seem like a great dad by the way. To even question some things tells me you are in tune with it all. I too often couldn't buy my kids 'stuff' or take great holidays, but it didn't matter. They remember the time I spent with them doing things; that was way more important. My ex doesn't have the relationship I do with them because he spent more time focusing on work and "paying them off" with gifts. Kids eventually see through all of that.
Happy birthday Charlie! You've got a great dad :)