Shawn Mendes Celebrates His 21st Birthday with Camila Cabello and Friends at N.Y.C. Party – Yahoo Entertainment

Shawn Mendes was certainly the “Life of the Party” on his 21st birthday.

To celebrate the milestone, the “In My Blood” singer rented out the 1 Hotel located near New York City’s Brooklyn Bridge on Thursday. The hotel, which sits on the East River, has a rooftop bar, lounge and pool that offers expansive views of the Manhattan skyline.

His sister Aaliyah shared photos from the bash, writing on Instagram: “happy belated birthday to this rockstar..who luckily happens to be my (now 21 year old) brother! love you soo much!”

Also in attendance at the party was Camila Cabello, Mendes’ collaborator on their hit single, “Señorita” and rumored girlfriend. Guests sipped on drinks named “The Señorita” (fittingly named after Mendes and Cabello’s song) and “The Pickering Gawd” (named after his Toronto hometown).

Hours earlier, Mendes seemed to reference the fact that he is now legally allowed to drink on his Instagram Stories. Alongside a photo of his hands marked with an “X” in black ink, he wrote, “No more of this s—.”

On Friday, Cabello shared a throwback polaroid of the pair on Instagram with the caption: “Happy birthday to this magic human, I love you!”

RELATED: Shawn Mendes and Camila Cabello Celebrate His 21st Birthday Hand-in-Hand in N.Y.C.

Earlier in the day, Mendes and Cabello, 22, were spotted holding hands as they left N.Y.C. bistro Jack’s Wife Freda.

Though they have yet to confirm their relationship status, Mendes and Cabello haven’t been shy about showing off their affection in public in recent weeks.

While vacationing in Miami at the end of July, the singers kissed in the beautiful blue water before Cabello wrapped her arms around Mendes as they floated around.

RELATED GALLERY: 21 Photos of Shawn Mendes That Will Make You Love Drunk, in Honor of His 21st Birthday

They were later seen holding hands as they wandered along the boardwalk enjoying the summer weather.

Rumors of their relationship began to fly following the debut of their steamy music video for “Señorita” in June. Adding fuel to the fire was PEOPLE’s confirmation just days later that Cabello had split from her boyfriend, relationship coach Matthew Hussey, after more than a year together.

After being spotted in Los Angeles holding hands and spending the Fourth of July together, things seemed to heat up when Mendes and Cabello were seen kissing in San Francisco later that month.

RELATED: Shawn Mendes and Camila Cabello Passionately Kiss During a PDA-Filled Beach Day in Miami

The musicians have been friends for years, and they also collaborated on the song “I Know What You Did Last Summer” in 2015.

Cabello recently talked about “Señorita” and Mendes, telling Variety, “I’ve known Shawn for such a long time, and it’s so much fun getting to work and do things with somebody who means a lot to you.”

In addition, the former Fifth Harmony member discussed her upcoming album and revealed she wrote it while she was “falling in love” — seemingly referring to her ex-boyfriend Matthew Hussey, whom she split from in June after more than a year of dating.

“Falling in love is like an infinite amount of levels and layers and angles,” Cabello said. “I fell in love and just opened up. Everything was written in present moment.”