If you don't have lemon syrup, combine the lemon juice, sugar, and water in a small saucepan and heat until combined. Do not allow it to boil. Cool before using.
Pour the vodka, amaretto, blood orange juice, and 4 tablespoons of the lemon syrup into a pitcher or a large mason jar with a lid.
Stir well, or my preferred method, shake in a mason jar.
Pour over ice and top with a splash of sparkling water.