The Simpson sisters – along with their husbands and friends – made merry amid the snow (okay, so it was probably fake snow), holiday lights and gargantuan candy canes as they marked Ashlee's birthday, just one month after she celebrated her marriage to Evan Ross, the 26-year-old son of Diana Ross.
Despite the warm temperatures, Ashlee got into the holiday spirit by wearing a faux leopard-skin jacket and snow boots.
"Last night made it @ashleesimpsonofficial favorite holiday Christmas in California. It was a snowy one. Happy birthday baby," her husband wrote on Instagram afterward.
Jessica, 34, also took to social media to share her feelings for her kid sister. "Happy Birthday Ashlee! There is no one I believe in more than you," she wrote, attaching a photo of her younger sis looking all glammed up. "Thank you for inspiring me everyday. I love you!!! #dirty30."
Happy Birthday Ashlee! There is no one I believe in more than you. Thank you for inspiring me everyday. I love you!!! #dirty30