The family of the six-year-old revealed the heartbreaking news late on Sunday evening with a statement on Toby’s social media account.
Toby battled stage four Neuroblastoma since his fourth birthday, but was declared to be in remission last year.
Leeds United helped the family in a campaign to raise £200,000 to pay for antibody treatment.
However, Toby was diagnosed with a brain tumour in the autumn after suffering from headaches and vomiting.
The family statement released on Sunday night read: “Our little warrior passed away yesterday at 1345.
“He was at home in the arms of mummy and daddy, with his big brother Ollie, his baby sister Sienna and all his family around him.
“He fought so hard to the end, he wasn’t in any pain and he was peaceful.
“I cannot even begin to explain how we are feeling right now, heartbroken doesn’t even come close.”
Leeds United owner Andrea Radrizzani said in a tweet on Sunday night: “RIP little angel Toby. I keep in my heart sweet and beautiful moments at Elland Road together. We love you angel. My prayers for you and your strong parents.”
The club’s Twitter feed read: “Heartbroken. The memories will live forever. We love you Toby x”
Liam Cooper wrote on social media: “Heartbroken to hear that my little mate has peacefully passed.. I will forever cherish the moments we spent together. Heaven has gained a beautiful angel. Your smile will live with me forever. Sleep tight little man I love you.”