Combine graham cracker crumbs, melted butter, and sugar in a bowl until well mixed. Use your hands to press the crust into ungreased 13"x9" pan, making sure the crust is even.
In a large bowl, use an electric mixer to beat together the cream cheese, sour cream, lemon juice and sugar until smooth. Set aside. In a separate bowl, add the whipping cream, vanilla, powdered sugar, and beat until stiff peaks form. Use a spatula to fold the whipped cream into the cream cheese mixture until completely combined. Spread the batter over the crust evenly.
Cover and refrigerate for 4-6 hours or overnight. Use a toothpick to draw out your flag design. Add the blueberry and cherry fruit filling to make the flag design. Top with edible star sprinkles.
Store any leftover cheesecake in an airtight container or covered with plastic wrap in the refrigerator for up to 3-4 days. The crust may become slightly softer over time, but the cheesecake will still be delicious.
Can I freeze the cheesecake? It's not recommended to freeze the assembled cheesecake as the texture may change once thawed. However, you can freeze the cheesecake filling separately and assemble the dessert just before serving.