Mahidol Adulyadej
Mahidol Adulyadej, Prince of Songkla or Mahidol Adulyadej the Prince Father or Mahidol Songkla was the father of King Ananda Mahidol and King Bhumibol Adulyadej of Thailand. He was also regarded as the father of modern medicine and public health of Thailand. He also founded the House of Mahidol or the present Royal Family of Thailand.
Prince Rangsit, himself a lesserclass prince , thought that to have someone of high prestige like Prince Mahidol supporting the movement to improve medical practice and public health in Thailand would generate more interest and probably more fundings. He strategically invited Prince Mahidol to a boat trip along the Bangkok Yai and Bangkok Noi canals. His office, Siriraj Hospital, was certainly on the route, and this was where he invited his halfbrother to stop and have a look around. Having seen Mahidols reaction to the poor state of the hospital, Prince Rangsit asked him if he wanted to help Mahidols answer at that time was, however, not very positive as he was concerned that he knew nothing about medicine. However, a few days elapsed and he agreed. He also decided he would study in the related fields himself.
Source: Wikipedia