Wang Mang
In 6 AD, Wang Mang selected Emperor Ping's cousin-once-removed (a great-great-grandson of Emperor Xuan), the one-year-old Liu Ying as the next emperor (to be known as Emperor Ruzi). However, using Emperor Ruzi's young age as a pretext, Wang Mang retained his role as acting emperor, while Liu Ying was given the title crown prince. Empress Wang was given the title empress dowager.