"Aunt Sang Lin, are you certain you haven't mistaken someone else? This lady, oh, this granny, is indeed Little Li's grandmother, her real one? Not just a sworn relation?" Lin Tian shook his head in disbelief, asking once more.
In Huaxia, people tend to believe in destinies determined by the Five Elements. If someone is born without a complete set of the Innate Five Elements or has a poor destiny, they must seek to complement it afterwards. Otherwise, their future path in life will encounter many obstacles.
There are many methods to supplement the Five Elements or destiny after birth; naming is one of them. Or establishing a kinship bond, where the eight characters of one's birth complement each other, can fulfill what's lacking. That's why Lin Tian assumed that the Miss Xiao Li had taken his master as a sworn grandmother.