2. Shou Sui
守岁;Shou Sui is when members of the family gather around throughout the night after the reunion dinner and reminisce about the year that has passed while welcoming the year that has arrived. Some believe that children who 守岁 (Shou Sui) will increase the longevity of the parents.
“一夜连双岁,五更分二年” means that the night of New Year's eve (which is also the morning of the first day of the New Year) is a night that links 2 years. 五更 (Wu Geng - a time period in Chinese time keeping roughly equivalent to 0300 - 0500 hrs) is the time that separates 2 years.