"Uncle Fraud" is what serious older brother Tom, 14, calls fancifying, irresponsible Uncle Claude--and even bedazzled Louise and Marcus, eleven and ten, have their doubts when Claude's promised Russian Easter eggs don't materialize after his departure. . . and a local mansion is burglarized. Say-it-isn't-so? You bet. As this heavy-handed contrivance has it, Tom is rendered comatose rescuing Marcus in a flood, and finally roused by Uncle Claude's mysterious, indecipherable "Ya tebya lyublyu": not a clue to the location of the elusive Easter eggs, but the Russian words "I love you." From the creator of Anastasia Krupnik, almost everything here is a disappointment except the kids' good instincts: Louise and Marcus don't implicate Uncle Claude in the burglary (they had shown him where the mansion's key was hidden); the chauffeur/caretaker's children are fiercely protective of their father--who, it emerges during the flood, was the culprit; and at the ensuing trial, Louise does her best for him too (he acted to help Tom, without thinking of himself). But the shift from Uncle Claude's peccadilloes to Tom's life-threatening injury is so out of key, and manipulative, as to cost the book all credibility and respect.