Kendall Jenner Is ‘Very Happy’ with Boyfriend Devin Booker, Says Source

Dave Benett/Getty; Michael J. LeBrecht II/NBAE via Getty Kendall Jenner and Devin Booker

After nearly a year of dating, Kendall Jenner and Devin Booker have taken the next step in their relationship.

A source tells PEOPLE that the model, 25, has her family's approval on her NBA player boyfriend.

Watch: Kendall Jenner and Devin Booker make relationship Instagram official

"What first seemed like a fun hookup, is now a relationship," the source says. "They are exclusive and Kendall is very happy with Devin."

"And her family thinks he is great. He was even invited to Kim's 40th birthday celebration in Tahiti," the source adds.

In October, the Kardashian-Jenner family celebrated Kim Kardashian's milestone birthday with a private island getaway. At the time, Jenner shared photos from the trip on Instagram with the caption, "locations a secret."

Kendall Jenner Instagram Kendall Jenner and Devin Booker

RELATED: Kendall Jenner and Devin Booker Go Instagram Official on Valentine's Day with Cute Photos

After first sparking dating rumors last April when they took a road trip from Los Angeles to Arizona together, Jenner and Booker, 24, made their relationship Instagram official on Sunday in honor of Valentine's Day.

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Jenner shared a photo of the couple leaning on a countertop sharing a silly moment together. The Keeping Up with the Kardashians star captioned the snap with a single white heart emoji.

Meanwhile, Booker posted a video of the pair spending time outdoors with a black dog amid a mountainous backdrop, before the trio are pictured laying atop a blanket on the grass. The athlete added an orange heart emoji to the post and tagged Jenner.

Devin Booker and Kendall Jenner

RELATED: NBA Star Devin Booker Reposts Kendall Jenner's Poolside Bikini Photo: 'Whew'

The duo has recently been spotted eating out together in Los Angeles and enjoyed a vacation in Idaho with friends Justin Bieber and Hailey Baldwin last summer.

Last month, the Phoenix Suns forward shared some love for his girlfriend on Instagram when he re-posted one of the model's poolside bikini photos.

"Whew," Booker wrote alongside the photo.

Jenner's original post, shared on Inauguration Day, was captioned, "a new day! a good day!"

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