Kate Middleton and Prince William are celebrating their fourth wedding anniversary on Wednesday as the world awaits the arrival of their second baby. Many are hoping that the day will become a double celebration for the royals, according to Mirror Online.

Kate and William walked down the aisle on April 29, 2011, at London’s Westminster Abbey in the presence of nearly 2,000 guests. Kensington Palace on Wednesday posted a link to footage of the royal wedding.

Nicki Macfarlane, the fashion designer who created the bridesmaid dresses for William and Kate's marriage four years ago, wished the couple on their anniversary by posting a picture of the original sketches of the dresses.

And four years later, it’s time for the Duke and Duchess of Cambridge to welcome their second child. The couple’s first child, Prince George, was born on July 22, 2013.

Kate, who was reportedly due last week, is reportedly continuing with her usual activities. The 33-year-old reportedly looked relaxed when she was spotted at the wheel of her car as she drove away from Buckingham Palace on Tuesday, when she reportedly also took her son, Prince George, for a dip in their private pool in the palace.

Meanwhile, St. Mary’s Hospital in Paddington, where the duchess is expected to give birth to the royal baby, has been busy making preparations. Parking restrictions outside the hospital’s Lindo Wing were extended on Wednesday. The restrictions, which began on April 5 and were due to end on Thursday, will now run through May 5.

"The parking restrictions will be extended at the moment for the next five days until May 5. If there is still no news by then it will be extended again,” a spokesman for the Westminster City Council reportedly said. "The signs will be amended possibly today, if not tomorrow morning."

Reports earlier this week claimed that Kate, who is speculated to be more than four days past her due date, may be considering induction. "The decision to induce is based on how she is feeling, her history and how the baby is managing. It’s a constant dialogue between the doctors, the midwives and Kate,” pregnancy expert Zita West told People Monday.