Ashlee Simpson Ross Throws American Girl Doll Birthday Party for 'Princess' Daughter Jagger's 6th

Ashlee Simpson Ross/Instagram

Ashlee Simpson Ross is celebrating her "little princess"!

On Friday, the singer, 36, and husband Evan Ross shared glimpses of the birthday party they threw for daughter Jagger Snow, who turned 6 years old. The American Girl doll–themed celebration saw Jagger and her friends enjoying treats around a colorful table where their favorite dolls also had seats next to them.

"Best girls party EVER. We love you @americangirlbrandofficial," Ashlee wrote on one slide of her Instagram Story.

In another post, the proud mom paid tribute to her only daughter, who wore a crown that read "Happy Birthday" for the occasion. "HAPPY BIRTHDAY to my little princess 🦄 You are the brightest light. We love you 🥳💚," wrote Ashlee.

Ross, 32, also shared snapshots from the party, plus a group photo in which their nieces — Jessica Simpson's two daughters 2½-year-old Birdie Mae and Maxwell Drew, 9 — smiled for the camera. "HAPPY BIRTHDAY MY LOVE!" the proud dad wrote.

Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday.

RELATED: See Ashlee Simpson and Evan Ross' Kids Ziggy and Daughter Jagger on Family Vacation

The parents also share baby boy Ziggy Blu, 9 months, and Ashlee is also mom to son Bronx Mowgli, 12, whom she shares with ex-husband Pete Wentz.

For Father's Day last month, Ashlee wrote to her husband on Instagram, "You are such an incredible father. I love watching you lead our family," alongside a photo gallery of Evan with Ziggy, Jagger and Bronx. "You always make everyone laugh, and have such beautiful lessons, and adventures for the kids. Thank you for being the husband, and father I dreamed of. We love you."

Evan also shared his own Father's Day message alongside an adorable video of Jagger and Ziggy: "There is Nothing better!!! Thank you for making me a Father ♥️ !!" Ashlee wrote in a comment, "Happy Father's Day to the best dad 💙 we love you."

In May, Evan celebrated his wife for Mother's Day, sharing a sweet photo of her with her three kids. "Happy Mother's Day baby! U r so amazing and I'm so lucky! Look at all this love you made!" he wrote in the caption.