'Oh..and by the way ... what was Alexei opinion abou him? After all he was just 1 year older than Johnnie, and also suffering of a disease'
Since Alexei was only five when they met, how likely is it that he would have remembered John very much? Also, John's epilepsy and mental condition don't seem to have become fully apparent until he was quite a lot older. Realistically, he was probably someone whom Alexei heard about from time to time via letters to his parents and people saying, 'You remember playing with Johnnie, don't you.'