Given the task definition and input, reply with output. In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.

Passage: He was promoted to lieutenant on 23 January 1962, captain on 23 July 1966, and major on 31 December 1972, At this time he was brigade major at HQ 3rd Infantry Brigade in Northern Ireland. As such he was responsible for the efforts to find Captain Robert Nairac who had been abducted by the Provisional IRA. Nairac and Jones had become friends and would sometimes go to the Jones household for supper. After a four-day search, the Garda Siochana confirmed that Nairac had been shot and killed in the Republic of Ireland after being smuggled over the border. On 13 December 1977 he was appointed a Member of the Order of the British Empire (MBE) for his services in Northern Ireland that year. On 30 June 1979 he was promoted lieutenant colonel, and on 1 December 1979, he was transferred to the Parachute Regiment. In the 1981 New Year Honours he was appointed an Officer of the Order of the British Empire (OBE).
Link Information: Captain Robert Laurence Nairac (31 August 1948 15 May 1977) Answer: 14
How old was Robert Nairac when Jones was promoted to lieutenant?