It was not the happiest of birthdays: At the time, her marriage to Prince Charles was crumbling. They would formally part the following year and divorce in 1996.
But that was all unknown to the Grammy winner, who told British talk show host Jonathan Ross that he played “Separate Lives” and “Doesn’t Anybody Stay Together Anymore?” at the bash.
“I didn’t know they were splitting up, no one told me!” he told Ross in an episode airing on Britain’s ITV this Saturday.
Collins, 65, also shares how he was closer to Charles than to Diana. “I was involved in [Charles’s charity] the Prince’s Trust,” he says. “I had been since 1983 and so I was kind of drawn to Prince Charles, who I think is a great bloke.
“I’m not a monarchist but I just think as a bloke, he’s a good bloke and I could see that at that time Diana was being a little bit of a loose cannon.”
In 1988, Charles asked Collins to organize his 40th birthday party. “We went to a Michael Jackson show at Wembley, and I was sitting behind [Charles] because I was a trustee,” Collins recalled. “When Michael Jackson was playing something, he turned around and said, ‘I’d like something like this at my party, will you organize it?’
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“And you think, ‘Yes, of course sir, yes,’ so I did but no, I just found people who could play Michael Jackson songs.”
Collins, who has just announced a comeback tour, also has an autobiography, Not Dead Yet, out now in the U.K.
The Jonathan Ross Show airs at 9.50 p.m. in the U.K. on Saturday.