Get Child Component seems to break if more components are added to the BP

I’ve come across a strange issue with Get Child Component nodes. I’ve made a slider system that functions perfectly: the slider calculates the difference between the beginning of the slider and the player’s cursor to determine where the cursor is positioned on the slider, and remaps that range to 0-1.

It then gets the children of the Slider, which is a scalable slider box which stretches to where the cursor is, and a value which is input with the slider’s value.

But when I duplicate the slider components, or add any new components to the Blueprint at all, the Get Child Component nodes break, as shown in here with the cast failing and the text and box not updating in the viewport:

Using Get Children Components and then an Array Get node similarly breaks. Pretty stumped with this one. I can post my project file if necessary.

The reason I need to do it this way is because I plan to have a ton of sliders - by not having to explicitly get the text and visual slider box for each slider, all I have to do it plug the parent component into the function each time to have it work.