The actress, 48, responded to a recent meme account post that said, "Nicole Richie & Cameron Diaz are sister in laws and I feel like we don't talk about that enough."
Diaz commented with a string of emoji, including one with an exploding head, as captured by Comments By Celebs.
"👯♀️?!? 🤯!!! 😉😉 @nicolerichie," Diaz wrote in the comments section of the post.
Some fans might already know that the two women are related by marriage. Diaz is married to Benji Madden, while Richie, 39, is married to the musician's twin brother and Good Charlotte bandmate Joel Madden.
Richie and Joel, 41, were married in 2010, while Diaz and Benji, 41, tied the knot a few years later in 2015.
Not only is Richie the actress' sister-in-law, but the aunt of Diaz and Benji's daughter Raddix.
A post shared by Comments By Celebs (@commentsbycelebs) on Oct 15, 2020 at 7:42pm PDT
Related: Cameron Diaz says she loves being a mom, calls Benji Madden an 'amazing father’
"Before, my baby was an excuse to stay home. Now I don't have to make that excuse," Diaz told Meyers. "It's just what it is, and I get to be with her."
"The best part of having to stay within our little bubble with this COVID situation is that her dad, my husband Benji, he gets to be home," Diaz added.
"He works from home, and so he gets to be with her as much as I do. Well, not as much, because he's working all day long, but he actually gets to come out of a meeting and give her a kiss and play with her for a little bit, where if he was going to the office every day he wouldn't be able to do that."
"We're just having a lot of gratitude for that," Diaz said. "And yeah, it's pretty wild."