Catherine Carey, Chief Lady of the Bedchamber is Sir James Perrot, MP's half sister-in-law's grandmother!

Sir James Perrot, MP
 

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Sir John Perrot
his father

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Sir Thomas Perrot, MP
his son

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Dorothy Perrot, Countess of Northumberland
his wife

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Lettice Knollys, Countess of Essex & Leicester
her mother

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Catherine Carey, Chief Lady of the Bedchamber
her mother