Add the condensed milk, lime juice, and cream cheese to blender.
Blend until smooth. Pour the contents of the blender into the pie shell.
Add heavy whipping cream, vanilla and sugar into a separate bowl and whisk on high speed until cream starts to thicken (about 2-3 minutes). Spread whipped topping generously over both key lime pies.
Put both pies in the refrigerator for about 2 hours before serving.
Notes
We typically make two pies - one to eat and one to share with the neighbors.