DURING THE SECOND HALF of their 53-year marriage, Robert B. Parker and his wife, Joan, settled into an unusual living arrangement. Parker, the creator of the hard-boiled Boston detective Spenser, lived on one floor of their big Cambridge Victorian; Joan, a powerhouse philanthropist, lived on another. The decision seemed odd to some, but to those who knew them well, their thinking was realistic and romantic at once.
The couple had separated shortly after their 25th anniversary and considered divorce. During their two years apart, they came to realize they each needed two things: their own space and each other. Buying the house just outside Harvard Square promised a novel way to get both.