Happy birthday, little Ace Knute Johnson. The now 3-year-old cutie belonging to Jessica Simpson and Eric Johnson, celebrated his big day with a fun-filled dinosaur-themed party on Thursday, June 30, 2016.

"Happy Birthday dinosaur! You complete me 💚 #3 #aceknute," the Jessica Simpson Collection designer wrote next to an adorable Instagram photo with her family.

She posed with her hunky former NFL player hubby and their two blondie kids, including the birthday boy and his older sister Maxwell Johnson, 4.

Happy Birthday dinosaur! You complete me 💚 #3 #aceknute

A photo posted by Jessica Simpson (@jessicasimpson) on

Jess added an action shot of her children playing around next to the huge layered dinosaur cake.

"Ace turns 3 and I feel prehistoric! #dinoparty #aceknute," the 35-year-old wrote.

Ace turns 3 and I feel prehistoric! #dinoparty #aceknute

A photo posted by Jessica Simpson (@jessicasimpson) on

She may have joked about feeling older, but boy did she look as hot as ever in a banana-leaf two-piece ensemble, showing off her toned tummy in a crop top and even more firm legs in a mini skirt.

Just last week, Jessica shared another sweet snap of her little ones playing by the pool.

"14 months apart and my blondies are trying to figure out which one will share or get thrown in ⚠️ ♉️♋️ #maxidrew #aceknute," she captioned the snap.

These siblings seems like two peas in a pod.