Prince Philip has been feeling the strain since his car smash, royal insiders claim.

The Duke suffered only minor injuries in the accident but has been struggling since, they say.

In a letter to a mom injured in the crash 11 days ago, he conceded: “I was somewhat shaken after the accident.”

But one source said: “He has been visibly more frail since he was pulled from the wreck.

“The truth is away from public eyes this has shaken him really badly — as it would anyone.”

Philip, 97, crashed his Land Rover as he pulled on to the busy A149 near the royal estate in Sandringham, Norfolk.

His car collided with a Kia driven by 28-year-old Ellie Townsend, who cut her knees.

Her nine-month-old son was unhurt but passenger Emma Fairweather, 46, broke her arm.

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