The fashion mogul wished her younger sis a happy birthday with a loving message.
The sisterhood is strong with these two!
Jessica Simpson took to Instagram to wish her younger sister, Ashlee Simpson Ross, a happy birthday with a sweet message.
"Ashlee -- I’m so proud to be your sister," the 37-year-old fashion mogul wrote on her post, sharing a cute picture of Ashlee with her kids, Bronx Mowgli Wentz and Jagger Snow Ross.
She continued, "I have always wanted to be as cool as you. I have never been inspired by anyone more than you! I love you so much! Happy Birthday."
Jessica and her husband, Eric Johnson, joined Ashlee and her husband, Evan Ross, for a birthday dinner on Saturday night at Beauty & Essex in Los Angeles.
Ashlee turned 33 on Tuesday, and for the official day, her husband posted a loving message and photo on Instagram.
"HAPPY BIRTHDAY!!!! To my BEAUTIFUL WIFE. I'm so thankful for you every single day!!! I love you with all my heart!!!" he wrote. "This picture is from one of the first trips we ever took together to CABO. I already knew then I wanted to be with you forever! I'm obsessed with you baby! Have the best day ever!"
Birthday celebrations with the Simpson-Ross crew are always close family affairs. Relive her 31st in the video below!