The diary of a 13-year-old girl revealed she had given her 'most precious thing' - her virginity - to her 16-year-old boyfriend, a court heard yesterday. The boy pleaded guilty to one count of unlawful sexual intercourse with a girl under 16. He pleaded not guilty to a charge of indecent assault, which was dropped when the prosecution offered no evidence. Eastern Court heard the incident happened on June 27 last year at the boy's home. The girl told a friend immediately afterwards about her first sexual encounter. She also recorded losing her virginity in her diary. The incident did not come to light until February, when the girl ran away from home. Her mother looked at her diary to check her daughter's friends' phone numbers and read that her daughter had given her 'most precious thing' to her boyfriend, the court heard. Magistrate John Brennan adjourned sentencing until September 1.