Meghan Markle and Kate Middleton
Royal fans predict that Kate Middleton will attend Wimbledon 2018 with sister-in-law Meghan Markle. Pictured: Markle and Middleton attend the first annual Royal Foundation Forum held at Aviva on Feb. 28, 2018 in London. Getty Images/Chris Jackson

Kate Middleton might attend Wimbledon 2018 with her sister-in-law, Meghan Markle.

The Duke and Duchess of Cambridge are the patrons of the lawn tennis club. Middleton is a self-confessed tennis fan. In fact, she admitted that in 2013, while she was heavily pregnant with Prince George, she begged for her doctor to allow her to watch the sports, but her request was turned down.

Now, royal watchers predict that Middleton will attend the tournament with the newest member of the royal family. The Duchess of Sussex was also spotted watching the tournament to support her friend, Serena Williams.

Williams and Markle's friendship started back in February 2014 when both played a game of flag football on DIRECTV's Celebrity Beach Bowl. The two immediately hit it off after their first meeting and became best friends.

"She quickly became a confidante I would text when I was traveling, the friend I would rally around for her tennis matches, and the down to earth chick I was able to grab lunch with just a couple weeks ago in Toronto," Markle wrote of Williams on her blog The Tig.

Since Markle and Middleton love the sports, many believe that the Duchess of Cambridge and Duchess of Sussex might attend the event together. The two were last spotted together at Prince Harry and Markle's royal wedding.

In related news, many noticed that Markle's manner of fashion has changed after her nuptials to Prince Harry. The former "Suits" actress made her debut as an official royal at Prince Charles' garden party where she dressed like Middleton.

Markle showed up in a rose-pink Flavia pencil dress with a tailored bodice, pencil skirt and silk-chiffon yoke and sleeves. She paired it with nude stockings, pumps and a Philip Treacy hat. Her get-up was reminiscent of Middleton's ensemble when she attended her first garden party in 2012.

Prince William and Middleton were not present at the event. The Duke of Cambridge was reportedly in Manchester Cathedral to mark the first anniversary of the Manchester Arena attack. Meanwhile, the duchess is still on maternity leave. According to Duncan Larcombe, it might still take a couple of months before Middleton return to her royal duties.

"It is traditional for new royal mums to take a six-month break from official engagements," Larcombe told Harper's Bazaar. "The wedding doesn't count because it was a 'family affair' but other than that, she will pick and choose her engagements. If she wanted, Kate could disappear into the background until October!"

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