Who is Meredith Oliver from Second Glance: A Novel and what is their importance?

Meredith Oliver is a geneticist. She works with couples who want to have children that are not afflicted with congenital defects and disorders that are passed down through DNA. Meredith is also Lucy's mother. Lucy is a little girl who can see ghosts. Meredith initially struggles with her daughter's abilities and believes she is psychotic. Over time, however, Meredith comes to accept Lucy's gifts.

As the investigation in Cecelia Pike's death continues, it is discovered that Cecelia's baby survived and grew up to have a child of her own. Meredith is this child. Shocked by the revelation, Meredith agrees to meet the remaining members of her biological past.