Sad news broke over the weekend with the untimely death of pop star Aaron Carter.

The singer, who first came to prominence at the age of 9 with his worldwide hit 'Crazy Little Party Girl', was found unresponsive in his bathtub on Saturday. He was 34.

In recent years, Carter has suffered from substance abuse and mental health problems. 2019 saw his brother Nick, of Backstreet Boys fame, and his sister Angel seek a temporary restraining order against him after Aaron had reportedly admitted "that he harbors thoughts and intentions of killing my pregnant wife and unborn child," according to Nick.

He revealed in the same year that he suffered from manic depression and had been diagnosed with multiple personality disorder, schizophrenia, and acute anxiety.

Nick posted an emotional tribute to his brother on Instagram, saying that his "heart is broken."

"Even though my brother and I have had a complicated relationship, my love for him has never ever faded," he said. "I have always held on to the hope that he would somehow, someday want to walk a healthy path and eventually find the help that he so desperately needed."

He added: "Sometimes we want to blame someone or something for a loss, but the truth is that addiction and mental illness is the real villain here. I will miss my brother more than anyone will ever know. I love you Chizz. Now you can finally have the peace you could never find here on earth…. I love you baby brother."

Backstreet Boys paid tribute to him during their London gig last night.

Other celebrities, including Aaron's ex-girlfriend Hillary Duff, songwriter Diane Warren and actress Melissa Joan Hart, also posted tributes to him. You can see a selection below.