Preheat oven to 375°F.
In a bowl, toss sliced pears, strawberries, and raspberries with lemon juice. Add remaining ingredients and stir gently to combine. Set aside.
In a bowl, combine flour and salt. Using two knives or a pastry blender, cut shortening into the flour. Gradually add water until a dough forms. Divide dough into two equal portions and form into two smooth balls. Roll each portion out onto a lightly floured surface until it forms a circle about 1⁄8 inch thick.
Place one piecrust into a 9-inch pie plate; finish the edges. Pour fruit filling into it.
Cut out leaf shapes from the second piecrust and arrange them over the top of the fruit.
Mix the egg with 1 tablespoon of water and brush over leaves and edges of the pie. Bake for 45 minutes, or until crust is golden brown and the filling bubbles in the center.