Though I try to have plenty of duct tape around the house it seems to disappear when Andrew is 'creating' something.
You know the rule; If it's moving and isn't supposed to - use duct tape.
If it's not moving and is supposed to -- use WD-40.
As a single-parent I often have one of those problems and duct tape has often come in handy. And, when you remove the duct tape and it leaves a sticky residue -- use WD-40 to clean it off.
Here are a few other uses of WD-40: lubricates squeaky doors, playground equipmen, teeter-totters, slides etc. Removes super strong glue from fingers and other surfaces, softenes and preserves leather furniture, keeps grandfather clocks lubricated and running smooth.