The two sisters wore bedazzled gowns for the special occasion.
Simpson also hosted the premiere of ‘LOL Surprise: The Movie’ with husband Evan Ross and daughter Jagger, which is on Netflix Oct. 8.
The cousins looked as cute as can be in matching maxi dresses!
Ashlee Simpson has given birth to her second child with Evan Ross.
Congratulations to Ashlee Simpson and Evan Ross!
This will be the couple's second child together, and Ashlee's third.
Ashlee is expecting her third child, a baby boy.
The 35-year-old star is expecting a baby boy with her husband, Evan Ross.
The singer and her husband, Evan Ross, will soon have a family of five!
This will mark the singer's second child with husband Evan Ross.
'You are so inspiring.'
Looking good, Simpson sisters!
The beauty mogul opened up to ET about her new makeup line and why her husband makes her want to stay youthful and vibrant.
Stars including Beyonce and Stevie Wonder were also in attendance!