Seth "introduces" to his "new brother" Ryan, the Chrismukkah.

Chrismukkah, is a holiday created for The O.C., the holiday, is invented by the second main male character : Seth Cohen. The holiday is a "fusion" between Christmas and Hanukkah. Seth, says he invented the : Chrismukkah (the word itself is a portmanteau arisen through the blending of the words Christmas and Hanukkah), when he was five years old, since he wanted a party, which celebrated, the beliefs of both his parents (his mother Kirsten in fact, is Protestant, while his father Sandy, is Jewish). Sandy and Kirsten were unable to decide which way to raise him, and so he began to use the word when he was just a child. He describes it as having "twice the resistance of a normal holiday" and being "8 days of presents followed by one day of many presents." It is supposed to " homage to the traditions of New York City and Newport Beach...[it] represents a blending of cultures, tolerance, inclusiveness, and celebration that the Cohen household practices."