Mamie | I--- Gros Cul Vieille

Lucienne, ever the good‑sport, raised her cane and shouted, “Allez, les jeunes! Let’s see if your steps are as sturdy as my… ahem … derrière!” Laughter rippled through the crowd, and a few brave youngsters hesitated, then giggled and took her hand.

Here's a possible approach:

Moving away from the "thin is best" narrative. i--- Gros Cul Vieille Mamie