That person looked like LiHuan kn the Flashback, I bet they met each other when they were kids! ε=ε=(ノ≧∇≦)ノ
No sister, the little kid is just a female relative's kid, likely a female cousin's daughter.
Well sister, I think you didn't read the 'in the Flashback' part :)
Sorry, I don't understand what you mean? The little girl is called niece, or in Chinese - sister's daughter, but Chinese people use the words niece and nephew with both their actual sibling's kids and their cousin's kids (I made another comment before explaining that cousins are often referred to with sibling terms in China and that a cousin's child will often be considered a nephew or niece). The family portraits and all other scenes of Lihuan's family show that he's the only child of his parents. He doesn't have a sister.
I don't mean his nephew dammit! xD I mean the person in YangYangs Flashback -.-
Well, then there's no relation between what I was saying and whatever you're talking about. In the flashback, there's only Lihuan, Yuyang and Lihuan's mom and dad. The person in the flashback that you're talking about is Lihuan, what does that have to with your original comment and my original reply?
Lihuan has a sister????....or was he refering to a cousin?