Lucknow, Oct 02: The CBI sleuths today grilled the mother and sister of slain poetess Madhumita Shukla at a government guest house here. The mother Shanti Devi and sister Nidhi were brought to Lucknow from their native Lakhimpur district earlier in the and interrogated for several hours, CBI sources said. Both of them, who had earlier given statements in the media against the prime accused and former state minister Amarmani Tripathi, were questioned by the investigating agency following Tripathi's admission yesterday that he had talked to Nidhi soon after the murder on May 9 last, the sources said. Meanwhile, the CBI continued the interrogation of Tripathi who is lodged in a room in a VVIP guest house here which had been turned into a temporary jail. Bureau Report