Mischievous mistranslation of the French expression Tant pis, tant mieux
Unknown, but has the feel of a Punch cartoon
Mum – 1960s
Pauline Iliff (Dixon) – mother of Mark, JM, G & Bel
In French pis is pronounced pee (and mieux m’yuh).
The phrase literally translates as “so much the better, so much the worse”. (In French, generally only the relevant half would be used.) People who like to appear sophisticated by using French terms while speaking English use it to mean something like “you win some, you lose some”