(click to enlarge)
Laws of the Grifter: Grifters are loyal to themselves only. When it's time to pack up and move on to fleece another audience, they'll drop a partner if they think it benefits them.
BONUS: Grifters have no problem using their family as props in their scam, and when a family member is caught committing a crime, the grifter naturally blames someone else. (h/t to SSBC)
(cartoons: top, Steve Benson, bottom, Tom Toles, via Gocomics.com)