The Meaning Of "And"

At some point, almost every cooperative board asks about the proprietary lease's "use clause." When it says the apartment can be used as a private dwelling by the lessee and the lessee's family, does that mean that both the lessee and the family must live there simultaneously? Some cooperatives have amended their leases, so that the language is unequivocal: "The apartment can be used as a private dwelling by lessee and simultaneously therewith, the lessee's family" (italics added). But there is a startling dearth of case law on this subject. In other words, what does "and" really mean?

Two lower court cases considered the issue in July 2016: 11 Wooleys Lane Housing Corp. v. Smith in Nassau County District Court and 50 Sutton Place South Owners Inc. v. Fried in New York County Supreme Court.