Clayton - the 22-year-old rising pop singer who was a protégé of Charli XCX - died on March 26 in his home from an aggressive form of bone cancer known as Ewing's sarcoma.
The sad news was reported by Billy's mother Becky Clayton, who wrote a touching tribute to her son on social media calling him "one of the most genuinely talented and special people ever."
"He held on for so long and had more strength than anyone could ever imagine. But his body would no longer allow him to live the life he so desperately wished for and his soul needed to escape to be free," Becky said. "Our hearts are broken into a million pieces and I have no idea how I will manage. But I know he is with me and with all the people who loved him. I was honored to be Billy's mum and will be forever and ever and again, next time around."