Here are kinship charts for a TV family (the Simpsons) and a book/movie family (the Potters). There are two versions of each of them, one with names and one without names.

Here, EGO is James Sirius Potter, the son of Harry Potter and Ginny. The family on the left is the Weasleys. The dotted line is a symbol that I made up to mean fictive kin of some sort, that is, a socially recognized relationship that is kin-like but isnt based on blood or law (marriage). Harry was raised by the Dursleys until he was 11, but Im not sure if he was legally adopted (if he was, Id link him by a line of dashes). After he went to Hogwarts he stayed with the Weasleys as much as possible. At one point Sirius Black says Hes not your son! and Molly Weasley replies Hes as good as!. Ron Weasley became godfather to James Sirius.