It’s an oldie but a goodie.

The start of a classic dad joke has gone viral on Twitter with users filling in the blanks for their own funny take on “Is there a doctor on board?”

Humorous Twitter account The Dad  is credited with starting the viral trend last week. The original tweet, posted Nov. 22, has been liked more than 63,000 times on the social media platform and shared more than 10,000 times.

It reads as follows.

The meme pokes fun at parental disappointment and how useless many professions would be in an in-flight emergency.

Twitter users from across the world have chimed in with their own versions, including a mother who chastises her daughter for majoring in sociology.

A disappointed dad and his cinematographer son.

The not-so-proud father of a marketing manager.

The difference between a doctor and a real doctor.

And this one which flips the meme on its head.