The singer, 36, and legendary music producer, 70, tied the knot last year.
The singer revealed their "beautiful" connection and also talked about her ties with Meghan Markle.
The couple tied the knot in an intimate ceremony with friends and family in London.
McPhee, 34, and Foster, 69, got engaged last year.
The couple publicly announced their engagement earlier this month.
The news comes just days after McPhee apologized to fans for missing performances of the Broadway show “Waitress” due to a “family emergency.”
The couple first met on "American Idol" in 2006.
His close friend David Foster gave fans an update.
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