Tamara "Tammy" Swanson is the mother of Ron Swanson. Tamara is also known as "Tammy Zero".
In "Ron and Tammys", Leslie Knope, Andy Dwyer, and April Ludgate show up at Tammy's house to ask her to help them rescue Ron from Tammy 1 (Andy's idea). Andy is especially fascinated by the room filled with guns, and Leslie asks her why she has all of them. She responds by telling them "This is America, isn't it? Then I don't have to answer stupid questions while standing on my own property".
Tamara shows up and challenges Tammy 1 to a "prairie drink-off" of highly alcoholic Swanson family mash liquor, saying Ron will return to the farm forever if she wins. Leslie enters the drinking contest to save Ron from his mother and ex-wife, but the liquor immediately makes her too drunk to continue. Ron, finally fed up over people controlling him, chugs the jug dry and tells both Tammys to leave him alone.