Sima Yue
Wang Dao's grandfather Wang Lan (王覽) and father Wang Cai (王裁) were mid-level Jin Dynasty officials, and he inherited from them the title Viscount of Jiqiu. He was the grandnephew of Wang Xiang. When he was young, during the late reign of Emperor Hui, he served on the staff of Sima Yue the Prince of Donghai. During that time, he befriended Sima Rui the Prince of Langye. It was at Wang's suggestion that Sima Rui slipped out of the capital Luoyang and stayed safe during most of the War of the Eight Princes in his Principality of Langye. When Sima Yue later became regent for Emperor Huai and commissioned Sima Rui to be the military commander for the area southeast of the Yangtze River, posted to Jianye (建業, modern Nanjing, Jiangsu), Wang volunteered to serve on Sima Rui's staff, and he became Sima Rui's chief advisor.