https://www.metv.com/stories/vincent-gardenia-shared-a-love-for-cooking-with-his-all-in-the-family-character

Gardenia was more than an actor - he was also a chef!

Jean Stapleton’s political awakening: How Edith Bunker sparked her fight for Women’s Rights (https://www.metv.com/stories/how-edith-informed-jean-stapletons-real-life-views)

Stapleton was a proud advocate for what she believed.

He loved to cook but hated being on this show. He was constantly annoyed he would have to sit and wait for his scenes. The article sugar coats his issues with TV when he says "he much prefers making movies the way they are shot." He became so annoyed that he left the show and was never spoke about again.
He was a great actor. Before Frank Lorenzo he was also Rue's husband in the episode "The Swingers." He also played a judge on an episode of Maude.