The Baaj Temple is at about 14 - 60. Go down the path, and you will dive into the water. Try to find your way from there.
Your second question i'm not to sure about. I don't think so.
OK, to find the boy. Firts make sure you found the father. The mother and son will ask you to find him. To find him, go one screen to the right, then another, still going to the right, then go up(a left turn for the character). The father is with a group of people, talk to him and he will rejoin his family. When you go back, you will realize that the boy is missing. Talk to the parents 3 times each or so. Then go to the left, above the save point and you will see a shiny path. Take that path up to the next screen. Go forward abit untill the path branches off in to 2 paths. Take the top one, the kid will be up there. Make sure you have the cloudy mirror, thats the entire point of this quest.
-Nothingface