The Lost Ones by Pete Prown

The third book in the The Chronicles of Dorro saga, THE LOST ONES finds the village of Thimble Down battling one crisis after another. A summer drought is wreaking havoc, while at the same moment, a child suddenly goes missing. And then another! Mr. Dorro and his young friends, Cheeryup and Wyll, must act before more children disappear ... something all the more eerie after the arrival of two strangers in the village.