If you don't add the alcohol, its a great shake for kids, my daughters love it. This will make enough for two children (3 and 4) to share. If you have a stronger blender, you can up the pints of ice cream and buddy fruit (and/or rum).
Put spoon size chunks of vanilla ice cream into the blender, half of your rum (I have found that a flavored rum, like raspberry flavor, is nice), and half of your Buddy Fruit and blend. Blend until there are only a few chunks left
Add the second half of your ice cream, rum, and buddy fruit. Blend until smooth.
If you like a thicker shake, just poor (or scoop) into a glass. If you like a thinner shake, you can add a tbl spoon of milk or so, and blend, adding as many tbl spoons as you want for the desired thickness.