Kate Hudson and her mom, Goldie Hawn, know how to have a good time!

Hudson brought her mom as her date to the Glamour Women of the Year Awards on Tuesday in London, and the two couldn't help but have fun in their hotel for a family after-party, according to Us Weekly.

Hudson was awarded the Glamour Entrepreneur of the Year Award and she showed up dressed for the occasion. The 36-year-old actress wore a super-sexy, super-low-cut red gown that had a secret, and very high, slit.

The two enjoyed their own private after party at their hotel, and Hudson decided to show off the slit in a video she posted to her Instagram.

In the video, Hudson spins and poses for the camera as she lifts up the front of her dress, revealing the slit, along with her entire leg and butt.

"Family Afterparty," the caption reads. "Best kind J"

As she sexily spins around in the gorgeous J. Mendel dress, you can hear Hawn laughing in the background and wishing the dress was able to do that at the event.

"Honey, the dress has to do that," Hawn explained. "Unfortunately there was no wind machine."