Not trying to one-up you, because I didn't even do this myself, but my brother passed a 13mm stone! He's single so we do
consider it his only child.
I mean, that's the size of a baby 3 weeks into the second trimester.
I don't envy you sir, but my older brothers seem to indicate that I may be joining you soon.
One swears his problem was drinking too much Martinelli's!