<Tr> <Th> Relatives </Th> <Td> Meredith Grey (sister - in - law) Addison Montgomery (ex-sister - in - law) </Td> </Tr> <Tr> <Th> Nationality </Th> <Td> American </Td> </Tr> <P> Amelia Shepherd, M.D. is a fictional character on the ABC American television medical drama Private Practice, and the spinoff series' progenitor show, Grey's Anatomy, portrayed by Caterina Scorsone . In her debut appearance in season three, Amelia visited her former sister - in - law, Addison Montgomery, and became a partner at the Oceanside Wellness Group . After Private Practice ended its run, Scorsone recurred on the tenth season of Grey's Anatomy, before becoming a series regular in season eleven . </P> <P> Amelia Shepherd is the youngest sister of Dr. Derek Shepherd, and like her brother, an excellent neurosurgeon . Her ambition to prove herself equal to her brother is only surpassed by her surgical skill . After graduating in the top of her class at Harvard and completing her surgical residency at Johns Hopkins, she comes to Los Angeles on a medical case and decides to stay after she is fired from her fellowship . She asks Naomi Bennett for a job when the two practices merge . She has known Dr. Addison Montgomery for many years and views her as a close friend and surrogate sister . As a young woman, she was addicted to prescription medication and crashed Derek's car while high . When she came home, she overdosed and was dead for three minutes . Derek saved her life, but was and still is angry with her . Amelia ended up sleeping with Derek's best friend Mark Sloan, following in the footsteps of her sister Nancy and her ex sister - in - law Addison Montgomery after making peace with Derek following his own shooting . </P>

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