The F-B-I says bone fragments found in a man’s yard are not those of Bobby Joe Fritz, who was five years old when he vanished from Campbellsport in 1983. Sheboygan County sheriff’s deputies recently asked the F-B-I to do advanced D-N-A tests on four small bones dug up in 1990 from the home of the late Michael Menzer. Investigators long suspected that Menzer abducted Bobby Jo and buried him at his property in Waldo — but he was never charged with those crimes before he died in 1990, while serving a 40-year sentence for killing two stepsons in a fire that destroyed the Waldo Mill. Investigators thought they could find Bobby Joe’s skeleton on Menzer’s land — so they dug it up after he died but found only four small bone fragments plus some decayed children’s clothes. That clothing is now being retested.