John Lee, a former top cop and security chief, is expected to be appointed Hong Kong's new chief executive by a committee of some 1,500 Beijing loyalists on May 8.
Hong Kong is dealing with a renewed Covid outbreak and requires all inbound travellers to quarantine for up to 14 days.
Tsang married three times and had a son with his first wife, Lan Di, and a daughter with his second wife, Barbara Tang.
Hong Kong is at the tail end of a deadly Omicron wave, killing some 9,000 residents and sparking an exodus from the city's business community.