Moist and fruity muffins

Ingredients
1/3 cup butter, softened
3/4 cup sugar
2 eggs 1-1/2 cups all-purpose flour
1-1/2 teaspoons baking powder
1 teaspoon ground cinnamon
1/3 cup milk
CREAM CHEESE FILLING:
2 packages (3 ounces each) cream cheese, softened
1/3 cup sugar
1 egg
3/4 cup fresh raspberries
3/4 cup fresh blueberries

STREUSEL TOPPING:
1/4 cup all-purpose flour
2 tablespoons brown sugar
1/2 teaspoon ground cinnamon
1 tablespoon cold butter