The mirror

Syaoran's four sisters are mentioned in the anime, and are only seen in the first Cardcaptor Sakura movie. His sisters are Fuutie, Shiefa (alternative spelling Xiefa), Fanren and Feimei. His mother and sisters are briefly mentioned in the Cardcaptor Sakura Manga when Sakura, Tomoyo, and Syaoran are trying to capture the Maze card. His mother's name is Yelan.
A common theme in Fan fiction is that Syaoran is a prince (with Sakura taking various roles). It may have been this which at least partially influenced Tsubasa: Reservoir Chronicle.
Syaoran's father is deceased. In the Anime it is implied...