‘Gripping … so powerfully emotional that at times I had to put it down to wipe my eyes’Mail on Sunday‘How do you say thank you to someone for giving you their heart? It is the greatest gift a person can ever give.’Marc is a promising young footballers of 15, growing up in Scotland. A few hundred miles away in England, Martin is a fun-loving 16-year-old. Both are enjoying their summers when they are suddenly struck down by debilitating illnesses. Within days, the boys are close to death.Although...