They grow up so fast.

A pair of Cork parents penned a cute note to the staff at a Cork burger restaurant to let them know they helped mark something of a milestone.

The crew of Son of a Bun shared the message on Twitter after the couple scribbled the note after paying for their meal at the Mac Curtain Street eatery.

The note, titled ‘Date Night No. 6’ reads:

‘Our now 21-month-old baby boy from date night no. 1 is officially a full member of the Son of a Bun family after ordering from the Kiddies Menu today!

My boy becomes a man!’

We love the Date night updates from this gorgeous couple……There’s no leaving him at home now you know that….? we just can’t believe it’s nearly 2 years ago since you’re little baby was born! ? pic.twitter.com/Y034amI1lT

— Son of a Bun (@sonofabuncork) September 16, 2018

Whether the burger-eating baba was a product of Date No. 1 has not been revealed, but either way, we salute their fine family tradition.