Cube the two pound cakes into bite size pieces. Set that aside.
Pour a 32 oz carton of heavy whipping cream into the mixer set up with the whisk attachment. Add the sugar and vanilla and mix at medium speed for about 3 minutes, or until the whipped cream is ready.
Layer the pound cake, a generous amount of tapioca pudding, the berries, then the whipping cream. Repeat until you reach the top of your trifle dish. Garnish with berries and nilla wafers.