Sia bought Maddie Ziegler a car for her 16th birthday.
The former 'Dance Moms' star - who has appeared in a number of the singer's music videos, on her album covers and more - couldn't believe her luck when the 'Chandelier' hitmaker rocked up at her house on Sunday (30.09.18) night with a white Audi in celebration of her sweet 16.
Taking to her Instagram account, Maddie uploaded a photograph of her perched against the bonnet of the vehicle, which was embellished with a huge red bow, and wrote: "sweet sixteen can't believe this car is actually mine !! (sic)"
The 42-year-old singer uploaded a series of photographs on her own account - including one of her and Maddie sliding across the bonnet - and wrote: "Happy Birthday to my most special noonoo @maddieziegler (sic)"
It's hardly surprising that Sia wanted to spoil the youngster as the teenager previously said she sees the blonde singer as her "second mom."
She said: "I've actually lived with [Sia] this year more than I have with my actual family, so it's fun. We have the best time together. She teaches me how to cook and new things about life ... It doesn't feel like work when we're together anymore. It's really just a bond that we have. She's my second mom."
And the pair are set to get even closer as Maddie will portray a younger version of Sia in the forthcoming biopic 'Sisters' - which stars Kate Hudson - out in 2019.
Speaking about Sia and Kate last year, Maddie said: "She's amazing I mean she knows how to do everything, she's the most incredible actor and she's probably my biggest inspiration in life - her and Sia, two girl empowerment, they're amazing."