A California family is offering a $25,000, no questions asked, reward for the return of sentimental, valuable jewelry stolen from them at the Westchester Hilton in Rye Brook. A pair of five carat blue sapphire earrings surrounded by 15 marquise cut diamonds, as well as a three carat diamond ring, were stolen from a purse, said private investigator Geoff Doyle of Doyle Carden Group in Manhattan.