Guy Newman Gilbey, who died at Melbourne, Australia, 19 July 2006, aged 53, was a scion from the family from which the Gilbey Baronets (cr 1893) descend. He was b. 23 Aug 1952, 2nd son of James Newman Gilbey (b. 1921), by his wife the former Celia Sparrow. He was a first cousin of James Gilbey (b. 1956), renowned as Diana, Princess of Wales's "Squidgy", &c. The Telegraph death notice says he was "Much loved by Siobhan and all his family". I have no details of a marriage, or of his issue, if any.
Source: Daily Telegraph 21 Jul 2006