Lemon Creamsicles

1 (14 ounce) can sweetened condensed milk
1/2 cup freshly squeezed lemon juice
1/3 cup sugar
1/2 teaspoon grated lemon rind
1 cup milk

Combine all ingredients and stir until sugar dissolves. Pour into 12 small (2 to 3 ounce) molds and insert sticks into center of each mold. Freeze 3 to 6 hours, or until solid.