Michael Zbornak is the son of Dorothy Zbornak-Petrillo and Stanley "Stan" Zbornak. He is also the grandson of Salvador Petrillo, Sophia Grisanti-Spirelli-Petrillo-Weinstock and Yolanda Zbornak. He was portrayed by Scott Jacoby in three episodes.
Michael works as a musician, and travels around the country on tour. Dorothy seems to cater to him slightly. In the episode Family Affair, Michael visits unannounced, at the same time Rose's daughter Bridget Nylund is visiting. Michael has left his job, and his lackadaisical attitude worries Dorothy. Michael and Bridget seem to clash, initially, as Michael's laid-back demeanor conflicts with Bridget's focus on her studies and desire for travel; however, Blanche sends the two out on a date, and they are discovered in bed together by Dorothy, Rose and Sophia.
In the episode My Brother, My Father, Dorothy mentions that Michael has joined the Boston Philharmonic Orchestra.
In the episode Mixed Blessings, Michael visits announces that he is engaged to Lorraine Wagner-Zbornak, who is black. Dorothy is accepting about Lorraine's race, but when she meets Lorraine and discovers her to be 20 years older than her son, Dorothy is upset. Ironically, Lorraine's family is upset that Lorraine is marrying a white man, but not that he is younger. The episode ends with Lorraine announcing she is pregnant, and Michael and Lorraine marrying.
In the episode All That Jazz, Michael announces that Lorraine has thrown him out of the house, and the relationship is over, but no reference is ever made to them having a child. Michael stays with the Girls, and Dorothy caters to him, taking care of his laundry, cooking and cleaning up after him, while he seems disinterested in finding work. Blanche tells Dorothy that he needs to take care of himself, and Dorothy suggests to Michael that he should find his own place, he gets upset and moves in with Stan. However, this doesn't last long, and the episode ends with Michael having found a new job, leaving town to take advantage of the opportunity.