Please answer the following question: Generate a question about the following movie plot: When tempestuous Mary Lennox (Margaret O'Brien), born in India to wealthy parents, is orphaned by a cholera epidemic, she is sent to live with her reclusive and embittered Uncle Archibald Craven (Herbert Marshall) and her ill-behaved, bedridden cousin Colin (Dean Stockwell) at their desolate and decaying estate known as Misselthwaite Manor. Dickon (Brian Roper), the brother of one of the house maids, tells her of a garden secreted behind a hidden door in a vine-covered wall. When a raven unearths the key, the two enter and discover the garden is overgrown from neglect since Craven's wife died there in an accident. They decide to keep their discovery a secret, and begin to restore it to its original grandeur. Under the influence of the Secret Garden, Mary becomes less self-absorbed, Colin's health steadily improves, and Archibald's curmudgeonly personality fades away.
A:
What was Martha Sowerby's occupation?