Wanna hear something odd? I get along with and like my mother-in-law. My husband feels the same way about my mother. In fact, she knew him before I did and they got along then. That just seems odd nowadays. But ain't it great?
<I>"...ain't it great?"</I>
Yeah,yeah sure-sure kid.
The "in-law" stigma thing is a stereotype that you can trace back to Plautus, Euripides, and cuneiform, probably.
Parents usually become controlling (even if they don't start out to intentionally <I>be</I> that way) and later, when additional characters enter the play, the dynamic is set up for a power struggle. Humans are pack animals.
What you present with, is a case of <I>QED</i> (Quod Errat Demonstrandum, for the Philistines - exception prooves the rule - a lot of fun, semantically) - but is guaranteed to draw a blank look from this crowd.
No it ain't great