[9:34] Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London
Britain's Prince William and his wife Catherine, Duchess of Cambridge, appear with their baby daughter outside the Lindo Wing of St Mary's Hospital, in London, Britain May 2, 2015. The Duchess of Cambridge, gave birth to a girl on Saturday, the couple's second child and a sister to one-year-old Prince George. Reuters/Suzanne Plunkett

Royal watchers wondered what the Duchess of Cambridge had to do to appear slim and sexy in just six weeks since giving birth to her second child, Princess Charlotte Elizabeth Diana. Apparently, Kate Middleton’s fit shape called for an expensive post-pregnancy regime.

The Duchess of Cambridge was photographed wearing skinny jeans and revealed her svelte form during the recent Festival of Polo. Kate Middleton showed no trace of her second pregnancy on her belly when she had her second public appearance at the polo match following the birth of Princess Charlotte. Apparently, according to an exclusive report from People magazine, the duchess had to hire an elite trainer to help her shed off the pregnancy fats.

According to the publication, a top London trainer, who has an elite clientele of A-listers, royals and executives, was brought in to work with the Duchess throughout her second pregnancy. "It's a lot of money, but you get a lot for the price,” a source revealed.

According to the source, the trainer’s package includes regular follow-up and tailored fitness routine. "The trainer checks in remotely with Kate by phone every day as well as seeing her in person once a week,” the source further revealed.

The Duchess of Cambridge also had to follow a strict diet plan involving organic fruits, veggies and lean meats. However, the food is reportedly prepared with a high-end twist. "The food is very elegant and actually feels like food you would eat at a restaurant," the source added.

Another source had also previously revealed to US Weekly that Kate Middleton frequents juicing to get rid of her post-baby fats. Kate’s sister, Pippa, had reportedly introduced juicing to the Duke and Duchess of Cambridge and they have since been hooked to it. The family source revealed that Kate consumes the juice in the morning to keep her healthy. The duchess had considered it as her go-to for an extra boost,” the source said.

According to Hollywood Life, Kate Middleton has also returned to doing yoga. She has reportedly also been spotted on several occasions shopping for organic foods at a farm shop near Norfolk called, “Back to the Garden,” where the Duchess of Cambridge gets her “fresh local produce.”

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