Wanderer vs. Stray

"Wanderers and Strays seem so similar, what's the diff?"
Well, there is one. They aren't used interchangeably. It's like rectangles and squares. Squares are a specific type of rectangle. Think of the 'rectangle' in this situation as a 'stray' and the 'square' as a 'wanderer.'

Strays are families, so if a wanderer has a family and lives with them, they are a stray. (As in, either they are a full/almost complete family unit with at least one parent and at least one litter of kittens or a large group of only related cats.)

A wanderer has recently left their family, or has no family living with them. Wandering siblings are known to travel together.

But what about the Aithne and Chandak cats, if Strays are Wanderers with families?
They took on more than just family, so they are a thing of their own, not a stray group.