Royal baby girl

Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. The Duchess of Cambridge, gave birth to a girl, the couple's second child and a sister to one-year-old Prince George. REUTERS/Suzanne Plunkett

Britain's Catherine, Duchess of Cambridge, holds her baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Suzanne Plunkett

Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Suzanne Plunkett

Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Cathal McNaughton

Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Cathal McNaughton

Britain's Prince William and his wife Catherine, Duchess of Cambridge, leave with their baby daughter from the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Suzanne Plunkett

Britain's Prince William carries his baby daughter in a car seat outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. REUTERS/Cathal McNaughton

Two workers return to Buckingham Palace after placing an easel in the forecourt to announce the birth of a baby girl to the Catherine, the Duchess of Cambridge, in London, Britain, May 2, 2015. REUTERS/Steve Par

Crowds gather outside Buckingham Palace after placing an easel was placed in the forecourt to announce the birth of a baby girl to the Catherine, the Duchess of Cambridge, in London, Britain, May 2, 2015. REUTERS/Steve Parsons/Pool

A ceremonial town crier holds a scroll after announcing the birth of a baby girl to royal fans and members of the media outside the entrance to the Lindo wing of St Mary's Hospital in London, Britain May 2 , 2015. The baby, their second child, weighed 8 lbs 3 oz and William was present at the birth, it said in a Twitter statement. REUTERS/Cathal McNaughton

A well-wisher holds a notice congratulating Britain's Prince William and his wife Catherine, Duchess of Cambridge, on the birth of their baby dayghter, outside the Lindo wing of St Mary's Hospital in London, Britain May 2 , 2015. REUTERS/Neil Hall

An easel is placed in the forecourt of Buckingham Palace announcing the birth of a baby girl to Catherine, Duchess of Cambridge, in London, Britain May 2, 2015. REUTERS/Steve Parsons/pool

An easel is placed in the forecourt of Buckingham Palace announcing the birth of a baby girl to Catherine, Duchess of Cambridge, in London, Britain May 2, 2015. REUTERS/Steve Parsons/pool

Crowds gather to see the easel in the forecourt of Buckingham Palace announcing the birth of a baby girl to Catherine, Duchess of Cambridge, in London, Britain May 2, 2015. REUTERS/Steve Parsons/pool

A ceremonial town crier announces the birth of a baby girl to royal fans and members of the media outside the entrance to the Lindo wing of St Mary's Hospital in London, Britain May 2 , 2015. REUTERS/Neil Hall

A ceremonial town crier announces the birth of a baby girl to royal fans and members of the media outside the entrance to the Lindo wing of St Mary's Hospital in London, Britain May 2 , 2015. REUTERS/Neil Hall

Members of the media set up outside the entrance to the Lindo wing of St Mary's Hospital in central London, May 2, 2015. The new baby will be fourth-in-line to the throne, behind brother George, father William and grandfather Prince Charles. REUTERS/Suzanne Plunkett

A ceremonial town crier holds a scroll after announcing the birth of a baby girl to royal fans and members of the media outside the entrance to the Lindo wing of St Mary's Hospital in London, Britain May 2 , 2015. REUTERS/Cathal McNaughton

A board stating the betting odds for baby names stands outside the entrance to the Lindo wing of St Mary's Hospital in central London May 2, 2015. REUTERS/Neil Hall

A woman poses next to a betting board showing the odds of baby names outside the Lindo wing of St Mary's Hospital in London, Britain April 29, 2015. REUTERS/Suzanne Plunkett

Members of the media set up outside the entrance to the Lindo wing of St Mary's Hospital in central London, May 2, 2015. REUTERS/Suzanne Plunkett