Cherie: Lawyer, wife and mum

Comfortable on the big stage - Cherie with Hillary Clinton

Cherie Blair, aka Cherie Booth QC, will become the first mother to bring a new-born baby into Downing Street since 1848 - when the then Prime Minisiter Lord Russell became a proud father.

Although she has cut back her work as a barrister since her husband became Prime Minister, she is still thought to contribute more than £100,000 a year to the family coffers.

Another role - Chancellor of John Moores University, Liverpool

Mrs Blair, a specialist in employment law, has also kept up the more traditional duties of a cabinet spouse.

On Monday she returned from a four-day trip to South Africa for the Commonwealth summit and on Thursday hosted one of her regular Downing Street tea parties for constituency children.

Mrs Blair receives about 250 letters a week.

Growing family

She is also an active supporter of a number of charities, notably Breast Cancer Care.

Then there is the small matter of looking after her three existing children, Euan, 15, Nicky, 14 and Kathryn, 11.

Victory in 1997

None of this has shielded her from press criticism.

Recent suggestions Mrs Blair was fed up with having to foot a £20,000 annual clothes bill drew a chorus of condemnation. The suggestions were denied by Downing Street.

Mrs Blair does not give interviews but once listed "keeping fit and enjoying my children" as among her recreations.

Cherie Booth was appointed a permanent part-time judge, or recorder, in June and could be a full-time judge within three years.

Working class roots

As a recorder, she has to sit at least 20 days a year as a judge.

Cherie Booth was brought up in a working class, Roman Catholic family in Bury, Lancashire, by her mother after her father, actor Tony Booth, walked out when she was two.

She got a first in her law degree at the London School of Economics and came top of her year in the bar exams.

Cherie met Tony while they were both training to be barristers.

She was an active supporter of the Labour party and there has been speculation he stepped up his involvement with the party to enable him to pursue her.

They married in 1980.

Cherie Blair fought and lost the no-hope seat of Thanet North in Kent at the 1983 General Election. In the same year her husband won his safe seat in Sedgefield, County Durham and began the climb to Downing Street.

The Blairs have frequently been compared to the Clintons but, while Hillary is stepping up her own political career by bidding to become a senator, Cherie may choose to put her legal career on the back burner to raise her fourth child.