Rinse and drain the crushed pineapple, mandarin oranges, and maraschino cherries. Let them sit in a colander for 3-5 minutes in the sink so there is no extra liquid.
In a large bowl combine the drained pineapple, mandarin oranges, and maraschino cherries.
Add the coconut and marshmallows and stir well.
Now fold in the sour cream and whipped topping until just combined.