Cut the pears into thick slices, about 1/4 to 1/2 inch thick. Use a small star-shaped cutter to punch out star shapes.
Toss the pear stars with lemon juice to prevent browning and keep them fresh.
Slice the watermelon into 1/2-inch thick slabs and cut out star shapes using the same cutter.
Quarter the strawberries after removing the stems.
In a large bowl, combine strawberries and blueberries and mix gently.
Carefully fold in the pear and watermelon stars, being gentle to maintain their shape.
Serve immediately or refrigerate briefly until ready to enjoy.