A grandson of Vitasoy founder Lo Kwee Seong is suing his father, claiming the man is a tyrant who lords over their estate on Shouson Hill Road and stubbornly refuses to switch on the air conditioning. Eugene Lo kept the 41,000 square foot property to himself - along with two drivers, three servants and two gardeners - while leaving son Patrick Lo Chun-yee largely confined to a bedroom with no en suite bathroom, the writ filed this week in the High Court said. The elder Lo also 'unreasonably refused' to let his son house his own driver in the 7,000 square foot home on the property, the claim said. The younger heir to the soya milk fortune also claimed he was not allowed to invite friends to the house while his father treated the home's common areas as his personal kingdom. '[The elder Lo] usually stays in the living and dining area of the building and loathes any other person staying there with him,' said the lawsuit. 'Further, the defendant does not allow any person to switch on the air conditioning in the living and dining area.' Patrick and Eugene Lo, who is the son of Lo Kwee Seong, each own half the estate, the writ said. Guests of the elder Mr Lo could visit but permission was required for anyone to visit Patrick Lo, which violated his rights as a co-owner of the property, he claimed. Eugene Lo had paid his son an annual HK$600,000 licensing fee for 'sole and exclusive' use of half the property, while the remaining half was to be shared by them both, the writ said. But the elder Lo had refused to give his son any money since October, according to the lawsuit. Patrick Lo's claim asked for damages valued at the property's monthly market rent of HK$400,000. Lo Kwee Seong established Vitasoy in 1940 when the fledgling business sold one soybean milk product that was delivered by bicycle. Its ubiquitous paper pack drink was launched more than 30 years later in 1975. Vitasoy became a listed company in 1994 with 300 leisure drink products on sale in more than 30 markets worldwide, including on the mainland, the United States, Canada, Australia, New Zealand and Southeast Asia. Eugene Lo's daughter Sharen is married to Lawrence Ho Yau-lung, son of gambling tycoon Stanley Ho Hung-sung. Members of the Lo family have founded other big name companies in the food industry. Victor Lo Tang-seong started Cafe de Coral and Dennis Lo Hoi-yeung established fast-food chain Fairwood in the 1980s.