In July, John B. Harris, and his wife, Stephanie Field-Harris, the scions of two prominent Chicago families, paid $13 million for a 10,000-square-foot French Renaissance Revival mansion on Astor Street. Built around 1895 for the real-estate developer W. D. Kerfoot, the four-story house has six bedrooms and eight baths.

According to information on file with the Cook County Recorder of Deeds, the residence last changed hands in 1989, when it was sold for $1,187,500 and contained six apartments. That buyer (the same person who sold the place this year to the Harrises) commissioned Marvin Herman and Associates to restore the building to a single-family layout and add the fourth floor. Because the most recent sale was conducted privately, the list price was unavailable. The seller is not identified in public records.

John B. Harris is a grandson of Neison Harris, who cofounded the company that introduced the Toni Home Permanent, and who, with the help of his siblings, later built up the Pittway company. Today Pittway, a division of Honeywell that manufactures fire and burglar alarms, is run by King Harris, who is Neison’s son and John’s father. Stephanie Field-Harris is descended from the department-store founder Marshall Field; her father, Marshall Field V, was formerly the publisher of the Chicago Sun-Times.

The Harrises could not be reached for comment, and the seller’s real-estate agent, Melissa McNally of Sudler Sotheby’s, did not respond to requests for an interview.

Photograph: Kim Thornton