Mix strawberry and berry blue Jello per the box directions and place them into bowls into the fridge for least 4 hours until set.

Break up Jello and place into Jello shot cups. A little of each color works well.

In a separate large bowl, sprinkle 2 envelopes of unflavored gelatin into 1/2 cup cold water and allow to sit for 5 minutes. After the gelatin blooms (it will look mostly dissolved and get wrinkly on the surface), add 1 cup boiling water and 1/2 cup rum (replace with water if you want non alcoholic); stir to dissolve.

Add the can of condensed milk and stir to combine; set aside to cool to room temperature. It must cool or it will melt the red and blue jello. Pour the cooled milk mixture over the red and blue Jello in the shot cups.

Place in the fridge overnight to set. Serve nice and cold for a fun summer treat.