The daughter of acclaimed Canadian author Alice Munro, who died in May, has written about the sexual abuse she endured at the hands of her stepfather and the pain it caused when her mother remained with him.

Andrea Robin Skinner, Ms. Munro’s daughter, wrote in the Toronto Star on Sunday that in the summer of 1976, when she was nine years old, her stepfather Gerald Fremlin “climbed into the bed where I was sleeping and sexually assaulted me.”

She also relayed her experience in an undated blog post, where she said later that summer that Mr. Fremlin “made me tell him about my ‘sex life’ – the usual innocent explorations with other children – and he told me about his sex life.”

In the post, Ms. Skinner wrote she soon told other family members about what happened, but not Ms. Munro: “I was terrified she would blame me anyway, as she seemed jealous of the attention I got.” Later, Ms. Skinner wrote, Mr. Fremlin exposed himself to her during car rides, discussed “little girls in the neighbourhood he liked,” and described her mother’s sexual desires to her.

Ms. Skinner, now an artist and a mediation facilitator, says she wrote a letter to her mother in her 20s describing what happened.

“My mother reacted as if she had learned of an infidelity. I had a sense that she was working hard to forgive me,” she said in the blog post. Ms. Munro remained with Mr. Fremlin, which her daughter said cast a dark cloud over the family, in the decades to come.

After reading a magazine interview in the early 2000s in which her mother described Mr. Fremlin as “gallant,” Ms. Skinner wrote that she decided to turn to police. “What I wanted was some record of the truth, in a context that asserted I had not deserved it,” she wrote, adding that she spent years estranged from her family.

Court documents show Mr. Fremlin pleaded guilty to the charge of indecent assault in 2005, was convicted by an Ontario court and sentenced to two months probation. The filings show the incident happened in Clinton, Ont., where the family lived near Lake Huron.

Mr. Fremlin, a cartographer and geographer, married Ms. Munro in the 1970s after her previous marriage to Ms. Skinner’s father, the Victoria bookseller Jim Munro, ended. Mr. Fremlin died at the age of 88 in 2013, the same year Ms. Munro received the Nobel Prize in Literature.

Ms. Skinner did not immediately respond to a request for comment on Sunday.