Up till 1950, Marceline Gillis' life has been anything but joyous. An immigrant mother from Canada and now in her early sixties, she's already survived the Great Depression, a World War, and caring for seven kids while almost being abandoned by her alcoholic husband early in their marriage. After years of disappointments, her bitter heart has increased during her hard life dealing with both poverty and her husband, Fred's drinking problem, which has left him frequently out of work. During the war, her adult son Tommy, suffers a permanent brain injury, leaving him with the mind of a child, who is also becomes her responsibility after his return from the war as being disabled.

Besides her other hardships, the Gillis family also suffers from a history of heart problems, often leaving the Gillis men in the family dying young. This was also true of Marceline's favorite son Andrew Gillis, who was rejected by the war and remained home because of a heart condition, only to die a few months before the house on Maple Avenue was finally purchased for her to live in. The ownership of the new house then goes to Johnny and Bernie, who also purchased the house using their GI Bills along with the money Andrew had saved during the war. But it is Andrew who always insisted the house be "Ma's house" wanting the house itself to make up for all the suffering she endured for her long and hard life, while doing her best to care for the large family.

After the large, run-down Victorian house on Maple Avenue is purchased, Marceline assumes she will be the landlady of the property, managing the house and its two rental units. But her two sons, Bernie and Johnny and their wives, have other plans for the house, feeling she is ill-equipped for the job. But instead of overseeing the new house, Marceline finds herself being treated as a "tenant" leaving her no longer the true matriarch of the family, which she had always been up till now. This house ownership disagreement sets up a small war within the tightly knit Catholic family, who never challenged Marceline's control over the family before. It appears that her the eldest son, Bernie, still harbors his own bitterness towards his mother, who abandoned him at ten in Canada, after she was herself was nearly abandoned by her husband Fred, who left for America to find work, failing to send for her and their six children to join him there.

As time passes, Marceline continues to dwell on her unfulfilled life and disappointments, becomes more fixated on ownership of the house, feeling that its possession will finally vindicate her from a life of tragedy and loss. After learning about a legal term "intent of ownership" by a real estate lawyer, Solomon Shulman, she realizes she can eventually gain ownership of the house by managing its day-to-day operations as the landlady of the house, because her sons both live elsewhere. With this new goal in mind, Marceline learns the skills needed to management of the large rental house, including the maintenance and banking, as her two sons' lives become too demanding to keep up with it on their own, because of their jobs, own homes and growing families. During this transition period, the interrelationship dynamics of the family play out in many humorous ways, while often working in Marceline's favor, despite the heartache and pain it causes to the rest of the family and neighbors who surround her.

Soon, the Gillis family suffers another major blow, the death of Fred Gillis, which sends Marceline into a two-year long mental stopper, unable to cope with his loss after a lifetime of abusing him. It takes the death of her second middle son, Tommy, to finally snap her back into reality, after which she vows never to let another loss in the family send her into an emotional tailspin again.

After years of living in small apartments as a family of nine, Marceline is finally living on her own for the first time in her life and doesn't like it.