The Maggie May hitmaker contributed backstage passes for an upcoming concert at London's O2 Arena, which made up one of several celebrity-based lots in a fundraising auction.
Soul icon Warwick gave an exclusive performance for 700 guests at the Butterfly Ball, helping to swell donations for the Caudwell Children charity, which provides support for disabled youngsters and their families.
Star guests at the event in London included Joan Collins, former British royal Sarah Ferguson and supermodel Caprice.
Trudi Beswick, the charity's chief executive, told the attendees, "We are delighted at the overwhelming support we received from all of our guests here this evening. This money is more important than ever as the demand for support increases. This will enable us to touch the lives of thousands of children. I can't thank everyone who donated tonight enough."