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He's become so close with them that he's been overheard calling Michael Middleton "dad" and intends to keep the Middleton family as a large part of his and Kate's life after the wedding, according to the Telegraph.
"Prince William has always been close to the Middletons and that will remain the case," says a senior royal source. "They will be as much a part of his family as the Royal family. There is no suggestion whatsoever that they will be airbrushed out of the picture.
"The Prince has made it absolutely clear that the Middleton family is incredibly important to him and he will do things his own way."
Royal-in-laws have long complained that once the wedding is over the Queen and other senior members of the Royal family "freeze them out" while their sons and daughters are expected to attend every Royal family event, including the traditional Christmas celebration at Sandringham.
After Capt. Mark Philips married Princess Anne his parents claimed that after the wedding it was as they "didn't exist" and they "never got invited to anything. Princess Diana's father Earl Spencer as well as Major Ronald Ferguson, the Duchess of York's father, never became part of the Royal family's inner circle either.
The royal source said, "The Middeltons will want to remain private, but they will still see their daughter as often as possible, and they will still see Prince William."
It is expected that the Middletons will be regular guests at royal residences. Kate's brother, James, and sister, Pippa, have both stayed at Prince Charles' home Birkhall on the Balmoral estate and last month Carole and Michael Middleton stayed there for the first time.
Prince William asked Michael Middleton got his daughter's hand in marriage before notifying his father and the Queen of his plan to propose to Kate, which shows how close he is with his future in-laws.
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