Ashlee Simpson Ross' Birthday Turns Into Sexy Double Date Night With Sister Jessica Simpson & Their Husbands

Ashlee Simpson Jessica Simpson birthday
Jerritt Clark

The mom of two turned 33 on Tuesday.

Happy birthday, Ashlee Simpson Ross!

The "Boyfriend" singer turned 33 on Tuesday, but she celebrated a little early over the weekend, spending Saturday night with loved ones at Beauty & Essex in Los Angeles.

Framing her face with super light, bleach blonde locks, the mom of two looked like a total rock star in a black jumpsuit, studded leather jacket and strappy silver sandals.

Her husband, Evan Ross, stuck close to her side the whole night, looking just as dapper himself in an all-black ensemble topped with a navy blue velvet blazer.

Jerritt Clark

Ashlee's big sister, Jessica Simpson, and her hubby, Eric Johnson, also stepped out for the soiree. Jessica went for an ultra-sexy look for the party: a mini LBD with sheer paneling in the middle that showed off major cleavage.

Jerritt Clark

Evan's older sister, black-ish star Tracee Ellis Ross, joined the gang as well, truly making for one happy, extended family at the birthday celebrations.

Jerritt Clark

Evan made it very clear that it was his wife's big day, showering her with plenty of PDA and stealing kisses throughout the night. (It is kind of his thing, after all.)

Jerritt Clark

At the dinner, the tight-knit crew dined on kale and apple salad, oven-braised chicken meatballs and salad, but it was the Gucci-themed cake that Jessica presented to Ashlee that was the evening's sweetest treat. “She was over the moon!” an eyewitness told ET.

The festivities moved to a second location, Warwick, later in the night. They stayed at the Hollywood hot spot, co-owned by Sylvain Bitton, JT Torregiani and Eli Wehbe, until about 2 a.m, sipping cocktails and keeping a low profile. "Evan never left Ashlee’s side," an eyewitness tells ET. "She was snuggling up to her husband all night long.”

After the soiree, Ashlee took to Instagram to share how grateful she was to hang with her ride or dies. "Such a FUN birthday party this weekend @ beautyessexla ! Beautiful night with beautiful people ?," she wrote.

On her official birthday, Evan shared a very sweet throwback photo of the pair in all their bohemian glory.

"HAPPY BIRTHDAY!!!! To my BeAUTIFUL WIFE. Im so thankful for you every single day!!! I love you with all my heart!!!" he wrote on Instagram. "This picture is from one of the first trips we ever took together to CABO. I already new then I wanted to be with you forever! Im obsessed with you baby! Have the best day ever!"

Seriously, these two couldn't be any cuter.

Ashlee's last few birthdays have all been close family affairs. Relive her 31st in the video below.

Additional reporting by Katie Krause