Mash pears with a fork in a bowl until desired consistency is reached.
Measure 1 1/2 cups juice from pears and pour into a saucepan; cook over medium-low heat until warmed, 5 to 10 minutes. Remove saucepan from heat and stir gelatin mix into pear juice until dissolved. Stir cream cheese and milk into gelatin mixture until smooth. Fold whipped topping into mixture; add pears and mix well. Spoon mixture into a 9x9-inch baking dish. Refrigerate until set, at least 1 hour.