According to reports, Ralph was considering pulling out of the event when Kate told organisers she wouldn't be attending but was told by his PR advisors it would "look terrible".
While a spokesperson from the Palace insists the Duchess was never due to go to the event, an insider told Vanity Fair an email from the fashion house was sent laying out demands on "where the Duchess would sit and who she should talk to, which might not have gone down too well," and could have been cause for her non-attendance.
William certainly appeared grateful, telling the 74-year-old on the evening; "I'm sorry my wife's not here, you probably would far rather you saw my wife."
"Not at all," replied Ralph.
After the event, his rep concluded: "Mr Lauren has only ever been enthusiastic about attending the event."
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