Complex sentence: When her husband died in 1829, she moved to Montreal, Quebec, Canada, to be with her daughters, Harriet Vaughan Cheney and Eliza Lanesford Cushing, who were popular writers in the nineteenth century.
Split into simpler sentences: When her husband died in 1829, she moved to Montreal, Quebec, Canada, to be with her daughters. Her daughters Harriet Vaughan Cheney (born about 1815) and Eliza Lanesford Cushing were popular writers in the nineteenth century.