She needed a cane to reach the witness box, and her hoarse voice was barely audible. But when Princess Diana's mother, Frances Shand Kydd, 66, began her testimony in the trial of former royal butler Paul Burrell on Oct. 24, she managed to drop a major bombshell: She and her daughter had not spoken in the four months prior to Diana's 1997 death, during which time Diana had returned her mother's letters unopened. Asked by Burrell's lawyer whether the estrangement "arose as a result of an argument that you and she had had about . . . the company she was keeping"--referring to close friendships Diana had before she dated Dodi Fayed, with whom she died in a Paris car crash--Shand Kydd replied, "No," adding that their relationship was "trusting."

Exactly how much trust Diana placed in her family is at the heart of Burrell's trial, which began Oct. 14 in London. The 44-year-old butler has pleaded not guilty to charges he stole about 280 items, including jewelry, dresses, personal photos and letters, from Diana's estate. The defense largely rests on the claim that Diana entrusted many of her most treasured belongings not to her relatives but to Burrell--who, it was revealed in court last week, stored the dress in which Diana died in his refrigerator before burning it in his backyard with her family's permission. Asked by prosecutor William Boyce where Diana's photo albums should be kept, Shand Kydd--whose own home on the Scottish Isle of Seil was burglarized while she was attending the trial--replied, "In her family house under lock and key ... I can promise you she gave away nothing other than gifts."

Di's sister Lady Sarah McCorquodale, 47, proved an even steelier witness. As an executor of Diana's will, she said she thought the late princess's 17 godchildren would prefer "mementos" from Diana's estate to the approximately $375,000 that Diana had specified should go to each child. Burrell's defense lawyer Lord Carlile challenged that assertion, noting that the godchildren "were not all from affluent backgrounds." Countered Lady Sarah: "There are not many paupers there."

The first defense witness is expected to be Burrell himself, who Diana's mother said had "misinterpreted" Di's famous description of him as her "rock." "It is a term which she used for many people," Shand Kydd said on the stand. "She called me her rock."