"She is Shifu's adoptive daughter"?
Looking at the source code, particularly the obsolete infobox parameters which are still in the code (why?) despite no longer doing anything, not only was Tigress listed as Shifu's "adoptive" daughter, he is also (still) listed as her adoptive father. Taken at face value, this means that they adopted each other!
Having read her bio, it is clear that describing her relationship with Shifu as "adoptive" (she adopted him) is one of the many misuses of this term which I have come across recently. The correct phrase is nearly always "A is B's adopted daughter" (A was adopted by B); if A is adult at the time of adoption, "A is B's adoptive daughter" (they adopted each other, by mutual agreement) is possible, but unlikely. Similarly, for other familial relationships the correct phrase is nearly always (e.g.) "A is B's adopted sister"; using "adoptive" in this phrase would mean that A and B were both active participants in / perpetrators of the adoption, which is seldom if ever the case.