“He had a very hard operation which lasted 7 hours but his heart couldn’t take it anymore, he was too weak to survive.”
She went on to add: “Heaven gained another angel, he was my rock, my everything. RIP Alex,” alongside a crying, angel and broken heart emoji.
Marcus, who was an idol for the teenager, shared a photo of Alex holding his book and typed: “My guy. I hope this book brought you at least a little enjoyment at the end.
“What an absolute superstar, fought until the very end. I was always thankful of your support @KipstaUnited.”