Tired of losing a kids cup or getting them mixed up. Label them and make different colors for each kid. Designed to fit these cups but my fit others as is or edit the 1 sketch to change size to fit. https://www.amazon.com/First-Years-Spill-Proof-Sippy-Ounce/dp/B000096M59
To edit the name select Sketch 2 and double click the Name in blue, the dialogue box will open at the right. Edit the text to what name is needed (there may be a character limit but the longest name I needed was 6 characters. Save the changes and they should appear on the model click finish and it will show the finished model. Export to an STL file and import into your favorite slicer.
I used a FLEX PLA at 200 and 15% Infill and slowed the print speed slightly. May work with other materials but I suggest something that flexes at least some so it can conform to the cup.
The author hasn't provided the model origin yet.