Ariana Grande and her family are mourning the death of her grandfather, who lost his battle to cancer on Tuesday.

The 21-year-old "Problems" singer took to Twitter to announce her grandfather's departure to her more than 16 million followers and express her sadness over his death. Grande also thanked her fans for supporting her through a difficult time.

"I lost you to the summer wind," Grande tweeted along with a broken heart symbol. "Thank you for your continuous love & light over the past few weeks... we did lose my favorite person to ever exist yesterday, my grandpa."

She continued: "If only y'all knew how amazing he was. My [heart] hurts so much. It's beyond broken, but I got to hold his hand and watch him find his peace. This is the hardest thing imaginable but I'm so grateful that I got to spend this time with him & my family. Taking care of him & loving him. We thank you so much for the continuous love."

Despite his passing, Grande still made her scheduled appearance on ABC's "Good Morning America" Wednesday. She explained on Twitter the she only made the trip to fulfill her grandfather's final wishes.

"The last thing he told her was to honor her work commitments and to go to NYC and sing her heart out on 'Good Morning America,'" a source told HollywoodLife.com. "Once the taping was done, she broke down in tears and cried on Ryan Seacrest's shoulder..."

The singer's brother, Frankie Grande - who is who is a houseguest on CBS' "Big Brother show," - was informed about his grandfather's death from producers. The rules of the show state that contest are not allowed to have contact with the outside world.

"Asked grandps last week if he wanted us to pull Frankie off bb & he said, 'No way! He's gotta play the game even though I don't understand it,'" Grande tweeted on Wednesday, but later deleted.

Despite her loss, the former "Sam and Cat" actress has been working hard to keep his memory alive by sharing several photos of her grandfather since his passing. Some photos date back to the 1940's, showing Grande's grandfather in his younger years.

#StayStrongAriana and #RIPGrandpaGrande were trending on Twitter Thursday.