While Khloe Kardashian and Will Sage AstorTristan Thompson's daughter True Thompson turns 5 later this month, her family marked the occasion early with an adorable shell-ebration.

On April 1, they threw her a party involving plenty of candy, pastel decorations and sea creatures. The theme of the bash: The children's TV series The Octonauts, one of True's favorite programs, which focuses on animal characters who go on undersea adventures.

"Yesterday, we threw True her 5th birthday party!!" Khloe wrote on her Instagram Stories on April 2. "Her birthday isn't until April 12th, but we decided to celebrate it yesterday."

The Kardashians star continued, "I'll hold onto the last few days of my 4 year old. True is obsessed with Octonauts so we had a pastel/octonaut extravaganza. Thank you to everyone who helped make this party that much more special."

Khloe and sister Kylie Jenner, who brought along her and Travis Scott's kids Stormi Webster, 5, and son Aire Webster, 14 months, shared several photos from the outdoor event, one of many extravagant children's parties the Kardashian-Jenner family has thrown over the years. True was also joined by cousin Dream Kardashian, 6—Rob Kardashian's daughter.

Meanwhile, Tristan and his and the Good American founder's 8-month-old son, whose name has not been made public, were not seen in photos from the bash.

Guests enjoyed swinging at an Octonauts-themed piñata, playing in a ball pit that also included toys, painting, making colorful slime and sand art and eating treats such as snow cones, cookies, cotton candy, cake push pops and ice cream sandwiches. True also received a large birthday cake to match the party's theme.

The party also featured performers in Octonauts costumes as well as real undersea creatures. There was a makeshift tide pool with starfish and rays. Guests could also build their own Octonauts-themed fish bowls and bring home a goldfish.

See photos from True's birthday party:

True celebrated her fifth birthday early on April 1, 2023. The theme of her party: Children's TV series The Octonauts.

True appears with her mom.

True appears with her aunt.

True gets a kiss from aunt Kylie Jenner.

True's mom appears at the party.

The birthday girl hangs out with her cousin, Rob Kardashian's daughter, and some party performers.

True and cousin Dream Kardashian make slime.

True's aunt appears with her and Travis Scott's son.

Kylie Jenner and Travis Sott's son appears at the party.

Guests were able to interact with real sea creatures.

Time for dessert from Hansen's Cake.

True's aunt appears with her and Travis Scott's daughter.

True's cousin appears with their grandma, aka their "Lovey."

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