My Mother-in-laws’s Cranberry Fluff

2 cans (16 oz each) whole berry cranberry sauce
2 cans (20 oz each) crushed pineapple
32 oz (4 half pints) heavy cream
½ bag miniature marshmallows

Drain cranberries and pineapple. Beat heavy cream until stiff. Fold in cranberries, pineapple and miniature marshmallows.