Pregnant in the heat! With scorching summer temperatures in effect, Kate Middleton left London's Kensington Palace for some R&R at her parent's house in Bucklebury, Berkshire, on Friday, July 12, a source confirms to Us Weekly.

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"It was just too warm in Nott Cott," the insider tells Us, referring to the couple's Nottingham Cottage residency, which lacks air conditioning. (On Saturday, July 13, Wales' highest 2013 temperature of 86.2 degrees was recorded). "She decided to spend the weekend with mum and dad. Much more comfortable."

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Indeed, her parents' residence boasts a pool, BBQ patio, and many cool rooms to relax in. While the 30-year-old mom-to-be waits to go into labor (her due date was July 11), the insider tells Us that "protection officers are visible from the street."

While Middleton cools off in Bucklebury, Prince William and Prince Harry are competing t the Cirencester Polo Club charity game on Sunday, July 14. The doting Duke of Cambridge will play on the same team alongside his brother and is prepared in case his wife needs him immediately.

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"William is relaxed," an aide tells Us, adding that a helicopter is not on standby. "Should Kate go in to labor he will go straight to London with a police escort."

And if she doesn't? "He will drive to Bucklebury and stay the night at the Middleton's house with Kate," the source explains.

This article originally appeared on Kate Middleton Leaves Kensington Palace for Bucklebury to Avoid Scorching Temperatures