That doesn’t sound right to me. Discounting leap years, you should turn 1 year old on your first birthday at the time of your birth (or considering the existence of leap years, 6 hours later than that, either the day of or the day before, depending).

I looked at it as: he has to keep running around it so he’s pissing from the right direction, presumably also accounting for properly leading it so his piss lands in it at just the right time. Still sounds messy to me.