Mysterious Map Piece

After you have removed the brick and clicked dad you need to work with dad and both stand on one of the red buttons behind him

Mysterious Map Piece

After you both stand on the red buttons you'll see a mysterious map piece to get to it you need to:

Get Purple Jewel Key

Open the Gate

Take Map Piece

Dig Out Tiles (12)

Tap the worksheet, then look to the right and remove that tile first and keep going removing tiles in that direction, you'll find the skull key which you use on the gate to the far right. Continue to the right and down until you find the lever. Tap the lever to get access to the next key, the red jewel key which is back and up. Tap the gate with the red jewel to unlock it. Continue downwards and to the right until you find the next lever, tap it to get access to the purple jewel key. Get that, then tap the gate with the purple jewel.

You can now tap the map piece.