Vegans

Shannon's dad, who has a slew of health problems of his own, recently became vegan. Brenda hates veganism like Tyler Perry hates making anything good, so she did not take this well.

She seemed to take it well; she started cooking vegan food for Shannon's dad and never really mentioned it to him. Naturally, however, there was major passive-aggressiveness at play.

Conveniently, everything Brenda made had something Shannon was allergic to in it, so she could never have any of it. It also recently came to light that Brenda had been sneaking eggs and dairy into his food because she does that sort of thing.

 Shannon's dad became vegan for health reasons, and after a month or so, got blood tests to see if it was improving his health. Bus since he's been unwittingly eating animal products, his lab results will likely show little change. This should give Brenda the satisfaction of insisting that veganism doesn't work.

Uh, right.