The presenters of BBC programme Operation Ouch, twins Dr Chris and Dr Xand van Tulleken, have engaged in a online row over who misbehaved at school.

Chris responded to a Tweet from a fan saying “Our daughter is bit upset tonight as she got told off at school for talking,” by posting a letter his parents got from his school, King’s College in Wimbledon Common, in December 1990.

Headmaster Colin Holloway wrote: “You will know from the number of cards your son has brought home for your signature and, in many instances, the discussion and correspondence we have had together that your son’s general conduct and attitude has not been satisfactory this term.

“I shall therefore require him to attend the Saturday morning detention class on December 8 from 9.30am to 11.30am.

“I hope I can have your cooperation in this matter. If you would like to discuss your son’s problems in any further detail I shall be glad to see you.”

But what Chris did not make clear, is that the letter concerned his twin Xand, not him.

Not willing to let the chance of being seen as the bad boy of the brothers go, Xand responded with another tweet, saying: “Such a gent my brother.

“What he doesn’t mention is that the letter is about me. He was doing fine.”

He then replied to the concerned parent to say that things will improve.

“I promise she is doing better than I ever was.

“Please reassure her that eventually it will be a funny story.”