Kathryn Hahn Gave Her Son A Lavender Bath — & It Went Horribly Wrong

Earlier this year, we wrote about a woman who incorrectly used coconut oil in her bath — only to quickly discover that hoisting herself out of a tub covered in oil was harder than finding time to actually take the bath. Now, there's one Bad Moms Christmas star sharing another beauty product you might want to proceed with caution before dropping in the water.

The cast of the upcoming film recently sat down with Ellen DeGeneres to chat about their real-life misfortunes with motherhood. Kathryn Hahn (who plays Carla in the movie) shared one particularly cringe-worthy experience with her son, Leonard.

“I wanted to have a spa time with him in the tub," she explained. "It was like, Oh, this is gonna be the coziest bed time ever. I’m gonna dim the lights; have candles — it’s gonna be a lavender bath. Didn’t know you shouldn’t use a straight lavender oil like that. It should be diffused.”

At this point her co-stars Kristen Bell and Mila Kunis, along with DeGeneres, have bursted into laughter. Hahn looked to DeGeneres: "Oh, so you did know?" she asked. The host gave a nod of affirmation, adding, "Well, because it burns."

Unfortunately, Hahn had to learn the hard way: "It was so relaxing for two seconds. Then, all of the sudden, it was like, bloody murder. Literally, grabbing frozen washcloths and putting...," she said, motioning toward the pubic area. "That was a fun night." Ouch.

Of course, Hahn surely isn't the only one to make this mistake. While plenty of oils are great additions to your beauty routine, some are just not meant for direct contact with skin, due to its high concentrations. And it's not just lavender: Experts recommend pairing eucalyptus, lemongrass, and bergamot with a carrier oil, like coconut oil, Argan oil, or even olive oil to avoid irritation. It's also best to do a spot test before putting anything on your skin.

That, or you can always stick to epsom salts.