"If anyone has any further unsolicited comments about *anybody* else's body, they can feel free to write them in permanent ink onto their own foreheads and swan dive directly into the sun," Ritter, 41, wrote on Saturday alongside a tweet Lynskey, 44, posted one day prior.
On Friday, Lynskey fiercely slammed body-shamers who have made "egregious" comments about her physique.
Alongside a since-removed tweet from author Ashley C. Ford, the actress tweeted, "The story of my life since Yellowjackets premiered. Most egregious are the 'I care about her health!!' people…"
"Bitch you don't see me on my Peleton [sic]!" she added. "You don't see me running through the park with my child. Skinny does not always equal healthy."
Lynskey and Ritter tied the knot in 2020. The two became engaged in 2017 and welcomed their first child, a daughter, in 2018.
If anyone has any further unsolicited comments about *anybody* else’s body, they can feel free to write them in permanent ink onto their own foreheads and swan dive directly into the sun https://t.co/5UyaHmR4JS
The couple's tweets come just a few weeks after Lynskey claimed that she was body-shamed on the set of "Yellowjackets" by a member of the show's production team.
In an interview with Rolling Stone last month, Lynskey said, "They were asking me, 'What do you plan to do? I’m sure the producers will get you a trainer. They'd love to help you with this."
According to the Rolling Stone interview, Lynskey's co-stars, including Christina Ricci, Juliette Lewis and Tawny Cypress, quickly came to her defense, with Lewis going so far as to write a letter to the show's producers.
Lynskey has opened up about her struggles with disordered eating and her body image in the past.
"I was losing my mind trying to conform to something that was not physically possible for me," she told PEOPLE in 2016. "I was very unwell for a long time. I had eating issues and at a certain point I was like, 'I'm not going to survive' -- not like I was on death's door or anything, but I was so unhappy and my hair was falling out."
The "Two and a Half Men" alum added, "I was like, 'I just need to look the way I'm supposed to look' and have faith that people are going to want to put someone in a film or on a show who looks like this. I did have to truly become comfortable with myself, because you can't fake it."