Are there key differences between Catholicism and Greek orthodoxy?

My son, who is a devout Catholic, is dating a young woman who is a devout member of a Greek Orthodox church. I wonder what are the differences between these faith traditions regarding the sacraments.

Regarding the sacraments the Orthodox generally hold similar theological understandings as Catholics. There are a few slight differences but the views are generally similar and all of the Orthodox sacraments are considered valid by the Catholic Church.

For more information:
Greek Orthodox Archdiocese of America

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