Gartner's eponymous magic Quadrant can be applied to pretty much anything, at least according to Gartner fellow, Steve Prentice. He applied Gartner's rigorous methodology to his own family.
The daughter goes top left (as in high maintenance, low value); the sheep (since he lives on a farm) are sadly bottom left - low maintenance/low value. Clearly not wishing to upset the missus, he's put her top right (high maintenance/high value). While the dog just needs a bone: ie low maintenance, high value.
So Steve, where would the mother-in-law fit?