Meghan Markle and Prince Harry are set to marry in May 2018. And the date couldn't be worse for poor Kate Middleton. She's due to give birth to her third child in April!

Prince William's wife has always taken pride in her appearance — and she's reportedly obsessive about her weight. But she recently caught flak for her dress at Pippa's wedding, with royal fans dubbing the look "frumpy." And you can bet the duchess isn't going to want to look matronly again.

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That puts Middleton in a tough position. Who would be happy about having to drop the baby weight in record time? Not to mention the fact that she can't even try on dresses right now!

According to royal sources, the duchess is feeling rather pressured. And some fans wonder if it was really fair to schedule the nuptials so close to her due date.

Kate And Pippa Middleton Many royal watchers felt Pippa Middleton outshined her sister at William and Kate’s wedding (Photo: Splash News).

But let's be honest. Prince William's wife has been down this road twice before. And she always loses the weight at rapid speed. She used the high-protein, low-carb Dukan Diet to slim down before her 2011 wedding.

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More recently, she hired a personal trainer to stay in shape while pregnant with baby Charlotte. And after her daughter was born, she went running and frequented the gym. She also relied on a healthy diet full of lean meats and organic fruits and vegetables to get skinny quickly.

Kate Middleton Pippa Wedding Kate Middleton was dubbed matronly at Pippa’s recent wedding (Photo: Retropix / Splash News).

"The food is very elegant and actually feels like food you would eat at a restaurant," a source told People at the time. "The whole program is very sensible – it’s not fad-based and is really focused on your overall health and well-being."

Middleton also joked in 2016 that "running after" her children helped her stay thin. Indeed, raising multiple kids is exhausting – even if you have nannies around to help. So even if Middleton does lose the weight she may not quite feel like herself.

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There are murmurings that Prince Harry and Meghan Markle will want to start a family quickly, which may be the reason for a short engagement. Other sources say the Queen didn't like the idea of Harry "living in sin" with the actress for too long.

Do you think it was wrong for Prince Harry to schedule the wedding right around Kate Middleton's due date? Let us know your take in the comments section below!