Photos: Timeline of William and Kate from College Sweethearts to Second Baby

Britain’s royal couple had their second child on May 2, a daughter who becomes fourth in line for the throne. Here are some highlights of the lives of Prince William and Kate Middleton, now Catherine, Duchess of Cambridge, from college sweethearts to proud parents of two.

September 2001: Prince William and Kate Middleton meet at St. Andrews University in Scotland where both are studying art history.

Prince William studies in the main university library on November 15, 2004, at St Andrews University, Scotland at the start of his last year of his four-year degree in art history. David Cheskin/Press Association via Getty Images

 

Christmas 2003: The pair reportedly become a couple after sharing a house with two friends. In March they are pictured together on a skiing holiday in Switzerland.

Prince Charles and his sons William (R) and Harry (L) on March 29, 2002 in the Swiss village of Klosters at the start of his annual skiing holiday in the Swiss Alps. Prince William celebrated his 21st birthday on June 21, 2003. Photo by Julian Herbert/Getty Images

 

Nov. 16, 2010: William and Kate’s engagement is announced. The prince proposed to Kate while on a private holiday to Kenya the previous month.

Woolworths's souvenir plate is seen to mark the anticipated engagement of Prince William and his girlfriend Kate Middleton. The leading high street store has designed a range of memorabilia including traditional china plates, thimbles, mouse pads and Will and Kate shaped pick and mix sweets in anticipation of the event. Photo by Woolworths via Getty Images

 

Prince William and Kate Middleton pose for photographs in the State Apartments of St James Palace on November 16, 2010 in London, England, after the announcement of their much anticipated. Chris Jackson/Getty Images

 

A close up of Kate Middleton's engagement ring on Nov. 16, 2010. The couple became engaged during a recent holiday in Kenya having been together for eight years. Arthur Edwards - WPA Pool/Getty Images

April 29, 2011: The pair wed in a lavish ceremony at London’s Westminster Abbey. William is made the Duke of Cambridge by his grandmother, Queen Elizabeth II, and Kate becomes the Duchess of Cambridge.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss as Bridesmaids Grace Van Cutsem (L) and Margarita Armstrong-Jones look on from the balcony at Buckingham Palace on April 29, 2011 in London, England. Peter Macdiarmid/Getty Images

 

(L-R): Miss Grace van Cutsem, Miss Eliza Lopes, HRH The Duke of Edinburgh, HM The Queen, The Hon. Margarita Armstrong-Jones, Lady Louise Windsor, Master William Lowther-Pinkerton. Back Row (left to right): Master Tom Pettifer, HRH Camilla, Duchess of Cornwall, Prince Charles, Prince of Wales, HRH Prince Harry of Wales, Mr Michael Middleton, Mrs Carole Middleton, Mr James Middleton, Miss Philippa Middleton, in the throne room at Buckingham Palace on April 29, 2011in London, England. The marriage of Prince William and Catherine Middleton was led by the Archbishop of Canterbury and was attended by 1900 guests. Hugo Burnand/St James's Palace - WPA Pool/Getty Images

June 30, 2011: The royal couple’s first overseas trip as a man and wife is a 9-day trip across Canada.  

British Prince William and Catherine, the Duchess of Cambridge receive hockey jerseys during a street hockey event at the Somba K'e Civic Plaza in Yellowknife, Northwest Territories on their nine-day tour in Canada July 5, 2011. Timothy A. Clary/AFP/GettyImages

 

Dec. 3, 2012: The palace announces that Kate is pregnant and being treated in the hospital for acute morning sickness. She is discharged from the hospital after three nights, telling reporters she is feeling “much better.” The palace later announces that the baby is due in July.

Britain's Prince WiIliam, the Duke of Cambridge and Duchess of Cambridge, leave the King Edward VII hospital in central London, on December 6, 2012. Catherine spent four days in hospital after she was admitted for treatment for acute morning sickness. Leon Neal/AFP/Getty Images

Feb. 5, 2013: The couple take a holiday on the Caribbean island of Mustique with Kate’s parents.

March 17, 2013: Kate tells a soldier at a St. Patrick’s Day parade that they do not know the sex of the child, but says she would like a boy but William wants a girl.

Catherine, Duchess of Cambridge, greets the 1st Battalion Irish Guards during St Patrick's Day parade in Mons Barracks in Aldershot on March 17, 2013. Adrian Dennis/AFP/Getty Images

June 4, 2013: William and Kate return to their wedding venue when they join the royal family for a service marking the 60th anniversary of the Queen’s coronation at Westminster Abbey.

Britain's Prince William, (L) his wife Catherine, Duchess of Cambridge, (C) and Prince Harry (R) arrive at Westminster Abbey in London, on June 4, 2013, for a service to celebrate the 60th anniversary of the Coronation Service. Leon Neal/AFP/Getty Images

June 15, 2013: The Duchess makes her last scheduled public appearance before the birth at the Trooping the Color parade.

Prince Harry, Catherine, Duchess of Cambridge and Prince William, Duke of Cambridge on the balcony of Buckingham Palace during the annual Trooping the Colour Ceremony on June 15, 2013 in London, England. The ceremony marks the Queens official birthday. Chris Jackson/Getty Images

July 22, 2013: Kate gives birth to a baby boy, weighing 8 pounds, 6 ounces, with William by her side.

A Town Crier reads an announcement about the birth of a baby boy at 4.24 p.m. to Prince William and Catherine, Duchess of Cambridge, outside the Lindo Wing of St Mary's Hospital in London, on July 22, 2013. Andrew Cowie/AFP/Getty Images

July 23, 2013: William and Kate take the baby home to Kensington Palace.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge, depart St Mary's Hospital with their newborn son at on July 23, 2013 in London, England. Oli Scarff/Getty Images

July 24, 2013: Royal officials say the new prince has been named George Alexander Louis. The announcement came after Queen Elizabeth II met her great-grandson. William and Kate then brought their child to her parents’ home outside London.

Royal baby boy is seen in a car seat outside Mary's Hospital in London on July 23, 2013. Leon Neal/AFP/Getty Images

April 7, 2014: William, Kate and George make their first official overseas trip as a family on an extended tour of New Zealand and Australia.

Catherine Duchess of Cambridge and Prince William, Duke of Cambridge travel on the Shotover Jet on the Shotover River on April 13, 2014 in Queenstown, New Zealand. The Duke and Duchess of Cambridge are on a three-week tour of Australia and New Zealand, the first official trip overseas with their son, Prince George of Cambridge. Chris Jackson/Getty Images

Sept. 8, 2014: The palace announces that Kate is pregnant with their second child and is once again experiencing acute morning sickness that forces her to cancel a number of official commitments.

Britain's Prince William greets well wishers on September 20, 2014 during his visit to Malta. Prince William took the place of his wife Kate for a visit to Malta this weekend because she is suffering from acute morning sickness. Matthew Mirabelli/AFP/Getty Images

Oct. 21, 2014: Kate resumes royal duties after her morning sickness eases. She and William welcome the president of Singapore to London at the start of a state visit. She carries out numerous official duties throughout her second pregnancy.

LONDON, ENGLAND - OCTOBER 21: Catherine, Duchess of Cambridge and Prince William, Duke of Edinburgh are seen during a ceremonial welcome for the President of Singapore at Horse Guards Parade on October 21, 2014 in London, England. Toby Melville - WPA Pool/Getty Images

Mar. 18, 2015: During a visit to a children’s center, Kate tells a volunteer she is due mid to late April. “Not long to go now,” she says.

Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge arrive at the XLP Mobile recording Studio on March 27, 2015 in London, England. Chris Jackson - WPA Pool/Getty Images

May 2, 2015: Kate gives birth to the couple’s second child, a baby girl, hours after she is admitted to London hospital.

Royal fans celebrate outside St Mary's hospital in central London, on May 2, 2015 after the news is passed that Catherine, Duchess of Cambridge and Prince William's second child, a daughter, was born. The Duchess of Cambridge was safely delivered of a daughter weighing 8 lbs 3oz, Kensington Palace announced. Leon Neal/AFP/Getty Images