Sarah Teather became an MP at the age of 29 after winning the normally safe Labour seat of Brent East in a by-election in September 2003.

She was given the role of Lib Dem spokeswoman for London and, against many predictions, managed to hold on to her seat at the 2005 general election.

She continued her ascent through the party ranks by taking on the local government brief and then education, becoming innovation, universities and skills spokeswoman when the job was split in two after Gordon Brown's Whitehall shake-up.

A Cambridge graduate who studied pharmacology, Ms Teather worked for the Macmillan Fund for Cancer Relief and was an Islington councillor before entering Parliament.