Text objects have a weird relationship with each other.
First, the definition of parent used in the OMV is misleading. There's real parenthood, where literally an object is the parent of some other object, as returned by the Object.parent property. And then there's ownership, where one object can own a collection of the other objects without being the parent.
For example, the Document object has a Pages collection, but the parent of a page is always the spread.
In the case of text objects, they all own each other. For example, you can say:
where myCharacter is a character. This isn't very useful, but it is valid. So, Character objects own Text objects and in that sense a Text Object can be parented by a Character object.
I've lobbied for the OMV to make the distinction between the two types of parent, but so far to no avail.