In an electric mixer, beat the cream cheese, sugar, sour cream, lemon zest, lemon juice and vanilla until smooth.
In another bowl, using an electric mixer, beat the heavy cream on medium-high until stiff peaks form, about 2 minutes. Fold the whipped cream into the cream cheese mixture.
Using a piping bag fitted with a star tip, pipe the mixture into each strawberry. Sprinkle with the graham cracker crumbs.