Who Is Jacob Sartorius? 5 Things to Know About Millie Bobby Brown's Boyfriend

With Millie Bobby Brown adorably flaunting her relationship with boyfriend Jacob Sartorius on social media, many are curious to know more about the 15-year-old singer.

The Stranger Things actress first sparked rumors that she was dating Sartorius, born Rolf Jacob Sartorius, in October when she posted a photo of him to her Instagram Story. After months of flirting between the two on social media, Brown, 14, posted a picture of herself cuddling a giant teddy bear with the caption, “Thanks for the bear” in January. Sartorius commented on the picture, “Of course.”

On Valentine’s Day, the pair exchanged sweet messages, and a week later, Sartorius wished Brown a happy birthday with a post declaring his love for “this beautiful girl.”

Here are five things to know about Sartorius.

1. He rose to fame by posting lip-syncing videos on the app Musical.ly

Sartorius became known on the Vine app at 11 years old after posting an anti-bullying video. He then got his musical start on the tween-friendly app Musical.ly where users can upload 15-second videos of themselves mouthing the words to popular songs, dancing or performing comedy skits. According to his website, he has built a following of nearly 20 million on the app.

I'll be standing next to you… Always🙈💗

A post shared by J (@jacobsartorius) on Jun 29, 2016 at 11:15am PDT

2. His 2016 single “Sweatshirt” charted on the Hot 100 in the U.S. and Canada

Sartorius’ debut single, “Sweatshirt,” was released in May 2016 and peaked at No. 90 on the Billboard Hot 100 and at No. 81 on the Canadian Hot 100. The music video for the single has been viewed more than 49 million times on YouTube.

3. He’ll be touring overseas soon

Sartorius wrapped his Left Me Hangin’ tour in February, but will head overseas for a few headlining shows in Europe in April before opening up for The Vamps on their U.K. tour through May.

work hard in silence, let success make the noise 🙏

A post shared by J (@jacobsartorius) on Mar 2, 2018 at 7:10pm PST

4. He’s been open about being adopted

In 2016, Sartorius posted a video to his YouTube channel opening up about how he was adopted.

“Although I grew up in Virginia like most of you know, I was actually born in Oklahoma,” Jacob said. “At the time, my birth parents weren’t able to take care of me, so they made a plan for me to be adopted. Luckily for me, I was blessed to be able to be adopted by two of the most loving parents in the world, my mom and my dad.”

He continued, “Being adopted is something I’ve never tried to hide or keep a secret. My friends and family have known all of this, but I think it’s the right time for you guys to know too. We’ve grown so much together in such a short period of time, and I know this is only going to make us closer.”

5. He’s been involved in some controversy

Sartorius shared a video message on Instagram in November and wrote, “Thankful. Just a kid out here working my butt off, so glad I have you guys with me. I wouldn’t be anywhere without you guys. Here’s to 2018 being the biggest year yet!!”

Fellow singer and America’s Got Talent alum Grace VanderWaal pointed out some flaws in his message by saying that people “3 times our years” have worked harder than either of them could ever imagine, and suggested social media helped him.

“No internet, no Spotify, no nothing that makes it so easy to gain so many fans in such little time, just dedication and pure hard work just pushing and pushing to make their dreams happen,” VanderWaal commented on his post, according to Teen Vogue. “Lip syncing on an app and manipulating young girls feelings and hearts is NOT ‘working your butt off.’ ”

She continued: “PLEASE get or stay educated on those who came before you to understand and realize your blessings. Stay humble brother.”

Sartorius also landed in some hot water with fans when Hailey Baldwin called him out on Twitter after a video surfaced of a fan asking him to give her three friends a shout-out. The video begins with the fan listing the three names of her friends as Sartorius says, “I’m sorry, I can’t remember that” before turning away.