Sturdy Cup Holder - Screw/Bolt Mount

I wanted to print a cup holder for my 3 year old son to use that attaches to his bed. Nothing I saw seemed to be sturdy enough to survive more than a day in the vicinity of toddlers, so I designed this one to fit that use case. The cup hold part slides over the mounting bracket that contains the hardware. It is designed to be removable, but with tight tolerances to achieve a very snug fit. Designed to use M5 pan head machine screws and M5 nuts.