March 4, 2014: "hey maddie, you want to play me?"
The beginning of it all: Sia reaches out to Maddie Ziegler on Twitter to inquire about the "Chandelier" music video. In a later interview with news.com.au, Ziegler marvels, "I didn’t even know she was making a video -- there was no audition, no anything. It was just a direct message from Twitter.”
May 6, 2014: A Star Is Born
Clearly, Sia's effort to reach Ziegler through social media worked out. Maddie first dons the famous wig in the public eye in the music video for "Chandelier." The viral clip amasses nearly 2 billion views on YouTube and leads to skits on Saturday Night Live, Jimmy Kimmel Live! and more.
Jan. 7, 2015: New Year, Same Outfit
The friends and collaborators kick off 2015 with a video for "Elastic Heart," featuring actor, performance artist and filmmaker Shia LeBeouf. Due to the ages of those involved -- LeBeouf was 28 and Ziegler was 12 at the time of release -- concerns arise over the cage-battle-themed clip. Sia apologizes, saying on Twitter that the actors were the only two she could think of that could represent what she wanted in the video.
Feb. 8, 2015: One, Two, Three... Performers
Though Sia doesn't win record of the year for "Chandelier" -- the honor goes to Sam Smith's "Stay With Me" -- she delivers a powerful performance of the song at the 57th annual Grammy Awards. With the songstress belting the vocals, Kristen Wiig joins Ziegler for a re-creation of the music video.
April 2, 2015: Big (and Little) Girls Cry
A little under a year after the release of "Chandelier," it is clear that the two aren't going to part ways anytime soon. The music video for "Big Girls Cry" -- the second track from Sia's 1000 Forms of Fear -- showcases Ziegler in the familiar wig and outfit, dancing at the forefront of the picture the entire time.
Sept. 10, 2015: Taking It to the Big(ger) Screen
A few days after showing up at the international film festival Venice Days, Sia confirms to Deadline that she is directing a self-based film with then-husband Erik Anders Lang. Ziegler is cast to play a younger version of the musician.
March 21, 2016: Cheap Thrills Earn Dollar Bills
In their third calendar year as collaborators, the friends team up for their fourth music video together. With Sia tucked away in the corner of the stage, Ziegler, accompanied by two male dancers, steals the show in the clip for the Billboard Hot 100-topping hit.
April 9, 2016: Two Chains
Ziegler takes to Instagram for a cute display of friendship between the collaborators. She posts a picture of her wearing some jewelry with the caption, "My two favorite necklaces." The first necklace has both Sia and Maddie's names inscribed with a heart in the middle and the second simply reads "sister" (the aforementioned film project was originally titled Sister and then renamed Music).
July 25, 2016: Tourmates
Sia taps Ziegler for the North American leg of her Nostalgic for the Present tour. "Maddie's presence adds a mischievous energy, as if replicated movements can't capture the heart behind those wide eyes and deranged smiles," Billboard's Jason Lipshutz wrote of a tour stop at New York's Barclays Center. "Sia fully understands how to make the live experience feel vital."
Sept. 5, 2016: Sia Pays Tribute to Orlando Shooting Victims With "The Greatest" Music Video
Opening with text reading #WeAreYourChildren typed in white font, the clip begins with more than a minute of white noise before the first notes of the track start playing. Including Ziegler, the video features 49 dancers in honor of the 49 lives lost at the Pulse Nightclub shooting in Orlando. Ziegler dons an all-black wig and rainbow-colored makeup on her cheeks for the song's visual accompaniment; the look later becomes the cover of Sia's This is Acting deluxe edition.
Sept. 19, 2017: Pony Up
Who knew that animated ponies kept their hooves on the pulse of culture? Sia, voicing Songbird Serenade in My Little Pony: The Movie, drops a music video for "Rainbow," which intertwines clips from the film and bits of Ziegler dancing. In a Billboard interview following the video's release, Ziegler raved about Sia: "What I love about her work, when she directs, is that it's nothing like anyone else before, and she just has a clear vision of what she wants."
Oct. 16, 2017: Christmas Comes Early
Sia announces her holiday-themed album, Everyday Is Christmas, out Nov. 17 of that year. The project is set to feature 10 original songs and showcases an appropriately decorated Ziegler as the star of the cover, decked out in plenty of red and green.
Nov. 1, 2017: Like (Second) Mother, Like Daughter
At WSJ. Magazine's 2017 Innovator Awards, the 15-year-old Ziegler tells People, "I’ve actually lived with [Sia] this year more than I have with my actual family, so it’s fun." She later discusses the large amount of time that the two have spent together over the summer working on the film. "It doesn’t feel like work when we’re together anymore," she says. "It’s really just a bond that we have. She’s my second mom."
Aug. 30, 2018: Cotton Candy Skies, Cotton Candy Hair
Supergroup LSD -- comprised of Labrinth, Sia and Diplo -- release a music video for "Thunderclouds." The trippy video features Labrinth driving his own personal cloud and Diplo driving a flying red car, of sorts. Ziegler, sporting a blue dress, an enormous blue bow in her hair and some pink in her wig for the clip, dances on top of the airborne vehicle.
Sept. 30, 2018: Speaking of Driving...
Sia gifts Ziegler a shiny new set of wheels for her 16th birthday. "Happy Birthday to my most special noonoo," Sia writes in an Instagram post, tagging Ziegler's account. The dancer posted a set of pictures on Instagram as well, one of which includes Stevie Wonder's 17-year-old son, Kailand Morris.