British doctor killed by falling rock on difficult California climb Dr Kiernan's father, Patrick, 60, who is also a doctor, said: "Climbing was a passion of his. He was on a six month break before he was due to start his training to be an oncologist. He had been to Thailand before the States. He and his climbing partner Luke, who he had known for years, were very experienced climbers and were extremely cautious. But it was a freak accident. Our thoughts go out to Luke, who is still in the States. The family are all here together and we are in shock. The 28 year-old leaves behind his twin brother Miles, also a doctor, as well as younger sister Dorcas, 23. Mother Sarah, 59, paid tribute to her son, telling the Evening Standard: "He is going to be missed so much. He really was a delightful person. He was handsome and so much fun. People fell in love with him all him time. He took everything in his stride and was a real wit. He was so clever and intelligent. He was a beautiful man. He really made a difference to people's lives, to the people he looked after during his training. We were about to go and visit him over there, we were due to fly out on Friday and spend a few days with him. He had been away for months, climbing around the world. He was very happy when we last spoke to him and was having a wonderful time. His death is the second in the park over the weekend and the fourth this season. Aleh Kalman, 19, was visiting the park on Saturday with a church group when he was seen swimming in the Merced River when he was swept over Nevada waterfall. "Yosemite is a wild place, and we want our visitors to enjoy the park but they also need to make good decisions," Scott Gediman, the park's spokesman, said.