Standing up for Toby! This Is Us' Chrissy Metz defended her costar Chris Sullivan for wearing a fat suit on the NBC hit during an appearance on Watch What Happens Live With Andy Cohen on Thursday, February 16.

Metz, 36, gave her two cents after a fan wrote in about Sullivan's "ridiculous" fake weight.

"I appreciate your opinion. And everyone has one and that's great. I just feel that — we tested a lot of gentleman who are bigger," Metz replied. "And I get it, people think the authenticity is kind of ruined by that, but Chris has been heavier and I think he does understand the plight of being overweight. And also he was the best man for the job. People wear prosthetics all the time. This happened to be weight as opposed to like a nose or a chin."

Metz can relate to Sullivan. She previously wore a fat suit on American Horror Story: Freak Show in 2014, where she played Ima "Barbara" Wiggles. "I wore a very large couch, prosthetic suit," she explained on WWHL. "So it's just kind of the name of the game."

Metz and Sullivan, 36, play engaged couple Kate and Toby on the drama. Their characters met at a weight-loss support group and Toby, who suffered a heart attack, has been supporting Kate since she started attending a weight-loss camp.

In November, Metz revealed that her contract actually includes a mandatory weight-loss clause. "That was a win-win for me," she told TVLine at the time. "Because it's one thing to try to do it on your own. But as human beings, it’s an ego thing: We’re more likely to do something for someone else."

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