Others noted as potential suspects in the crimes include Sullivan, possibly in retaliation for being ordered to clean the windows on a hot day; the day of the murders was unusually hot—and at the time she was still recovering from the mystery illness that had struck the household. A "William Borden", suspected to be Andrew's illegitimate son, was noted as a possible suspect by writer Arnold Brown, who surmised in his book "Lizzie Borden: The Legend, the Truth, the Final Chapter" that William had tried and failed to extort money from his father. However, author Leonard Rebello did extensive research on the William Borden in Brown's book and was able to prove he was not Andrew Borden's son. Although Emma had an alibi at Fairhaven, (about from Fall River), crime writer Frank Spiering proposed in his 1984 book "Lizzie" that she might have secretly visited the residence to kill her parents before returning to Fairhaven to receive the telegram informing her of the murders.