Edna Hodge, Mrs. Bower's neighbor, is played by actress Jan Miner. She also played Madge the Manicurist in Palmolive dishwashing liquid commercials for over 20 years.
This episode appears to be based on the 1991 murder of Mary Bowe by her granddaughter Tracey Bowe and Thomas Steed. Bowe stole a $2,400 retirement check from her grandmother so she and Steed could buy drugs. Mary threatened to press charges, so Tracey held down Mary's legs whilst Steed held a piece of plastic and a pillow over her face. The boyfriend then slit the victim's wrists to make her death appear to be a suicide.
ETA: Although this story does concern a grandmother who was possibly murdered by her granddaughter, none of the actual details resemble the Mary Bowe case at all.
Chris Noth (Detective Mike Logan) & Lynda Gravatt (Antoinette) also worked together on Another Ham Sandwich (2012) (episode 3.14) and Dollhouse (2006) (episode 5.10).
Chris Noth (Detective Mike Logan) & Tovah Feldshuh (Danielle Melnick) also worked together on Doubt (2010) (episode 1.18), as Peter Florick & Lena respectively.