Hannah Seymour was in fact, Hannah Seabourne. Her father was George Seabourne, a convict who came out on the Forfarshire in 1843. Her mother was Bridget Murphy, a convict who came out on the Blackfriar in 1851. George and Bridget married in 1852. Hannah was born in 1860; her mother died in 1865 when Hannah was less than 5 years old. For the next 6 years her whereabouts are unknown, then she is found at the Orphan School. She won a prize under her true name - Hannah Seabourne. The records of the school show both names, but the name Seymour has not occurred with any other family member.
Hannah was my great grandmother's (Valier aka Violet Seabourne) half sister.