“雨水”到 拜丈人 拉保保 Culture Insider: 5 things you may not know about Rain Water

No.4 Finding godfather 拉保保

Another old custom is to find a godfather for little kids. Rainfall brings vitality to the earth; therefore people in the past believed that this practice would give their kids healthy and safe growth.
雨水这天在民间还有一项特具风趣的活动叫“拉保保”（保保是干爹的意思），取“雨露滋润易生长”之意。

The custom can be traced back to the health services of the past when many children’s diseases could not be cured at all. Therefore, parents wanted a godfather to shower their blessings and good luck on their children. This old practice was popular in Sichuan area.
旧时医疗健康条件较差，很多儿童疾病不易治愈。因此家长给孩子“拉保保”，希望儿女顺利健康成长，这在四川非常流行。