The little boy was robbed and would like you to help him gather some items that he losses.
He needs 1 3-Carat Diamond, 1 Witherless Rose and 1 Immortal Heart. There is a Trader near the East exit of Morroc that sells Witherless Rose. The other two items can be obtained from monsters in the Pyramid. Or you can buy the 3 carat diamond from a NPC located in front of the Coal Mine Dungeon (check related quest section).
Once you give the little boy the items, he will offer to help you. Accept his offer and he will lead you to another dimension where you can communication with the dead.