Final answer:
Twyla asks Roberta about her mother in an attempt to reconnect and bridge the gap created by time and differing perceptions of their shared past from their time at St. Bonny's orphanage.
Step-by-step explanation:
The circumstances under which Twyla asks Roberta about her mother during their encounter in the Howard Johnson's restaurant suggest that Twyla is reaching out in an attempt to reconnect over their shared past. This moment in the narrative underscores the complex nature of memory and personal history as seen throughout their evolving relationship, as well as the impacts that their upbringing at St. Bonny's has had on them. Since Twyla and Roberta were once inseparable friends at St. Bonny's orphanage, the inquiry into Roberta's mother could be seen as Twyla's way of trying to bridge the gap that has grown between them due to diverging paths and different memories of shared experiences, such as those surrounding the character Maggie.