In trifle bowl or very large glass serving bowl, prepare both packages of gelatin as directed except omit 1/2 cup water. Place in refrigerator and cool, about 30 to 40 minutes.
Sprinkle 1 jigger of sherry over ladyfingers. Arrange ladyfingers in the bowl containing the gelatin by covering the bottom and sides of the bowl. Refrigerate until firmly set.
Arrange berries over gelatin and ladyfingers. Prepare the custard as directed. Cool custard until it is only slightly warm, approximately15 to 20 minutes.
Gently cover the fruit; gelatin trifle, with custard; be careful not to crush the fruit. Refrigerate until cooled and set about 2 to 3 hours.
Just before serving, whip heavy cream and syrup together into stiff peeks. Do not over sweeten, cream should be lightly flavored and rich. Layer whipped cream over top of trifle.
Garnish with fresh fruit, sprinkles or mint leaves.
Note: Keep refrigerated until ready to serve; the whipped cream will fall if not served soon. Also, if you use too much sherry, gelatin will not set.