I've seen it! ATL to DEN on Delta, three obeasts in a row in front of me and across the aisle. What I could gather from their (loud) conversation and apparent ages and genders was mother, father, college-aged daughter, but it was really difficult to say considering they all had almost the exact same proportions and body size, carrying a lot in the upper back and gut/gunts. They were seated when I boarded, all jammed up against one another, a solid wall of flesh from where the father was pressing into the wall and the mother jutting into the aisle (did I jostle her with my carry-on? maybe I did, maybe I didn't). It was kind of like Tetris, with the daughter's side boob/underarm fat pressing over to the right and the dad's paunch under and to the left. I was planning on hate watching them through the airport, but Denver is a large one and I'm a fast walker and they legit came to a dead stop at the gate to stare around and decide where they were going, so I didn't.