Madonna and her 5-year-old daughter, Lourdes, made a rare public appearance together Tuesday night in London, where they joined models Helena Christensen and Kate Moss and singer Natalie Imbruglia to kick off fashion photographer Mario Testino's exhibit at the National Portrait Gallery, reports the BBC and the Associated Press. Madonna's husband, British film director Guy Ritchie, accompanied them. (Lourdes's father is Carlos Leon, a former boyfriend of her mother's. Madonna and Ritchie also have a son, Rocco, born in August 2000.) Madonna and child are but two of the Peruvian-born photographer's subjects, whose exhibit, which opens to the public from Feb. 1 to June 4, is cosponsored by Burberry and Dom Perignon in association with Vogue. "People love to be photographed by Mario," American Vogue editor Anna Wintour is quoted as saying in a statement from the gallery. His show, Testino's first at a major London institution, presents more than 120 color and black-and-white portraits, including those of Robbie Williams, Catherine Zeta-Jones and Elizabeth Hurley. Special sections of the exhibition are devoted to Kate Moss, Gwyneth Paltrow and Madonna, as well as Testino's portraits of Diana, Princess of Wales, photographed shortly before her death in 1997. Born in Lima, Peru, into a family of Irish, Spanish and Italian origins, according to his gallery bio, Testino moved to London from Lima in the early 1980s, where he began his formal training in photography.