LONDON (Reuters) - Zara Phillips, the granddaughter of Queen Elizabeth, is to marry her England rugby union boyfriend Mike Tindall, the royal family announced on Tuesday. No date was given for the wedding of Phillips, 29, the daughter of Princess Anne and her first husband Mark Phillips, and her 32-year-old long-term partner. The announcement comes a month after it was announced that Prince William, elder son of Prince Chares, would marry his long-term girlfriend Kate Middleton in London next April. Phillips was considered something of a royal rebel as a teenager, having her tongue pierced as a teenager. However she went on to follow in her mothers footsteps enjoying a successful horse riding career. In 2006, she won the individual gold on her horse Toytown at the World Equestrian Games in Germany and helped Britain win a team silver. Her success led her being voted BBC sports personality of the year. Princess Anne rode in the 1976 Olympics and was European Champion in 1971, while Mark Phillips won an Olympic team gold in eventing in 1972. They divorced in 1992. Tindall is also a well-known sportsman, having played more than 60 times for England and having been part of the team that won the World Cup in 2003.