I was browsing roblox wiki about tweens when i noticed some functions that you could use with tween. Here's a few of them:
- FindFirstChild
- ChildAdded
- ChildRemoved
But before we go any further I'd like to define the word tween in case anyone misunderstands it.
Tweens are used to interpolate the properties of instances. The Tween object itself controls the playback of the interpolation. Creating and configuring tweens is done with the TweenService:Create
The functions i listed are only meant to be used if you have objects inside of a parent. Why would you want to store objects inside of a tween?

2 comments
Those are just general function usually listed in functions etc. Yet the first parameter TweenService:Create() requires the Instance to Tween, you can reference an Instance through those methods if not already nested in a variable
Because you can, I guess