London:
Hans Kristian Rausing, who was being questioned in the wake of his wife's death this week, is a member of one of Europe's richest families - a fortune built on the Tetra Pak, maker of a better milk carton.
His Swedish grandfather, Ruben, began producing milk cartons in 1952, and in 1963 gave the world a flat-topped carton that can be packed and shipped like bricks. The development revolutionized the packaging and distribution of milk and fruit juices worldwide.
Ruben's sons - Hans and Gad - took over the business when he retired and built the company into an empire. Hans, father of Hans Kristian, later sold his share of the business to Gad for 4.5 billion pounds ($7 billion).
The Rausing family is known for its sizable donations to charity, by some reports giving more than 150 million pounds away over the past few years. The senior Hans Rausing has also made headlines for his large donations to Britain's Conservative Party.
Hans Kristian and his wife had been well-known charitable donors and his sisters - Sigrid and Lisbet - also are heavily involved in philanthropy.
Sigrid - who owns and publishes Granta magazine - has won awards for her human rights work and created a trust to support human rights.
Lisbet, a historian and researcher, has taught at Harvard and is a cofounder of Arcadia, a grant-making fund to protect endangered nature.