Who is Laura Fairlie, Lady Glyde from The Woman in White and what is their importance?

Born on March 27, 1829, Laura Fairlie (Lady Glyde), is nineteen-years-old with long, light-brown hair and turquoise blue eyes. Laura is engaged to forty-five-year-old Sir Percival Glyde, a Baronet, an engagement sanctioned by her parents, the late Mr. and Mrs. Philip Fairlie. Though Laura loves Walter Hartright, she is forced to marry Sir Percival Glyde on December 22, 1849. She is declared dead on July 25th, 1850 just after her 21st birthday, but she has actually been institutionalized under the name Anne Catherick (Anne is buried in her place).