Aww,Surfwin aunt they cute?

In honor of Gigi Hadid's 28th birthday, Bella Hadid shared photos of the supermodel with her 2-year-old daughter Khai in an Instagram post. One picture showed the mother-daughter duo rocking similar hairstyles during an outdoor playdate, while Gigi snuggled with her mini-me while getting her makeup done in another snap.

"Happy birthday to @gigihadid," Bella wrote on Instagram April 24, "my best friend, my confidant, my teacher, my logic, my most favorite chilling partner." While revealing her special nickname for her niece, Bella called Gigi "the gift that keeps on giving because you brought me my most favoritest gift in the world miss Khaibaloo."

The 26-year-old continued, "Calm cool collected kind loving hard working angelic creative brilliant fun thoughtful PURE, the list of all of the reasons I love you could go on for days."

In her post, Bella also explained why she was absent from Gigi's birthday weekend celebrations at Walt Disney World, which was attended by close friends such as Queer Eye's Antoni Porowski and makeup artist Patrick Ta.

"I wish I could have felt better to celebrate you at Disney but I am always with you in spirit and your #1 cheerleader 365 days a year," she wrote to Gigi. "I love you so much it hurts."

Bella also included childhood photos in the sweet note, prompting Gigi to reveal the nickname she has for her younger sister in the comments section.

The birthday girl wrote back to Bella, "I LOVE YOU SO MUCH MY BELLOOONI."

Gigi welcomed Khai with ex Zayn Malik in September 2020. Since then, Bella has developed a special bond with her niece, often sleeping over at Gigi's home to spend time with the little one.

"I want to be with the baby and I want to wake up early and be there," Bella told E! News in a 2021 interview. "I never knew that I could have this much joy in my life. She's the biggest gift. Our family has changed in the best way for the better."

She jokingly added, "Are there full time aunties out there?"

And when it was time for Gigi to pen her own birthday tribute to Bella that year, the Guest in Residence founder described her sibling as Khai's "forever protector."

"She's my baby sister but also a firecracker of a spiritual body guard," Gigi noted in an October 2021 Instagram post. "I have so much pride watching you take ownership of your growth and fulfillment, and I know everything that you have created for yourself will bring you the year of joy and light you deserve!!!!!!"

Keep reading to see more photos of Gigi, Bella and Khai.

Sign up for E! Insider! Unlock exclusive content, custom alerts & more!