Preheat your oven to 350°F (175°C).

In a large mixing bowl, combine the white cake mix, water, vegetable oil, and eggs. Mix until well combined.

Pour the batter into a greased 9x13 inch baking pan and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean.

Remove the cake from the oven and let it cool in the pan for about 10 minutes.

Using the handle of a wooden spoon or a skewer, poke holes all over the top of the warm cake.

In a separate bowl, mix the sweetened condensed milk with the strawberry Jell-O until dissolved. Pour this mixture evenly over the holes in the cake.

In another bowl, prepare the blue raspberry Jell-O according to the package instructions and let it cool slightly.

Pour the blue raspberry Jell-O over the cake, ensuring it seeps into the holes as well.

Refrigerate the cake for at least 4 hours, or until the Jell-O is set.

Once set, spread the whipped topping evenly over the cake.

Garnish the top with sliced strawberries and blueberries to create a patriotic design.

Slice and serve chilled.