In regards to Prince John, he made regular appearances with his family until his 11th birthday when his condition, epilepsy, became too severe. Unfortunately back in the 1900s, epilepsy was poorly understood and nearly everyone who had it as severe as John, if they couldn’t be cared for at home, ended up moving to a mental hospital for the rest of their life. When reading about John I have read one of his grandmothers kept a garden especially for him on the Sandringham Estate. Also his mother let local children befriend him which was against Royal protocol at the time. After his death one of the children, Winifred Thomas, was given a number of John's books, which Queen Mary had inscribed, “In memory of our dear little Prince.”
It seems that quite a few of the family were sympathetic to John, apart from Prince Edward who described him as an animal and said his death was “little more than a regrettable nuisance”. He also wrote a hateful letter to Queen Mary which has since been lost. What a prized dick he was.