"Sunday Family Dinner... @jenniegarth @gabriellecarteris @bh90210 #nomakeup," she proudly captioned the snap.
While most fans commented to cheer the women on, a few haters left rude remarks, including one who accused the actresses of "trying too hard to be relevant."
As usual, McDermott, 52, wasn't having it.
“I love how you haters have private accts!! Let’s see what you trolls look like ya cowards!!!” the "Slasher" actor blasted back.
It's just the latest incident of McDermott defending his loved ones against online meanness.
In March, he stood up for Spelling and the couple's five kids after critics said the children appeared "overweight and unhealthy" in promotional photos of them eating muffins on Spelling's Instagram page.
"I am sick and tired of everybody taking a shot at my wife, Tori Spelling. Just because she’s a celebrity they think they can say and do whatever they want,” McDermott said in a video.
McDermott and Spelling share five kids — Stella, 10, Hattie, 7, Liam, 12, Finn, 6, and Beau, 2.
“She posted about a snack, it’s a snack people. Haven’t we given our kids a snack before? Cakes, cookies whatever. It’s a snack. She’s a great mom. We’re great parents. Our kids eat healthy. They eat a lot of fruits and vegetables, and occasionally they have a snack,” he said.
He also called out trolls in January who said his kids looked "chubby" and "shabby," among other cruel remarks in the comments of one of Spelling's pics.
"I am absolutely horrified and disgusted by the comments being left about my children," he wrote in a lengthy response. "Body shaming and bullying my children??!! What is wrong with you people??!!"
To those who left uplifting messages for his wife, McDermott shared a special note of gratitude.
"Thank you to all the people who came to our defense," he wrote. "You're all kind compassionate souls. Down with the haters!! Up with love!!"