Jessica Simpson went all out for son Ace's third birthday party!

The 35-year-old hosted a dinosaur-themed bash for the toddler, complete with a volcano-shaped cake.

"Ace turns 3 and I feel prehistoric!" the fashion mogul captioned one shot from the event, adding, "Happy Birthday dinosaur! You complete me."

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Jess also posted a rare family photo on Instagram that included daughter Maxwell, 4, and hubby Eric Johnson, 36.

This clan is pretty picture perfect! Scroll through the gallery below to see more of Hollywood's cutest kids.