Complex sentence: She grew up in Bray, Berkshire and was taught to drive, aged 11, by her brother Stirling; however, she started her sporting career on horseback, becoming well known as a successful show-jumper and member of the British showjumping team.
Split into simpler sentences: She grew up in Bray, Berkshire and was taught to drive at the age of 11 by her brother, Stirling. But she started her sporting career on horseback, becoming well known as a successful show-jumper and member of the British showjumping team.