Who is Mamie Laverock? Meet the actor who plays Rosaleen Sullivan on When Calls the Heart

Rosaleen Sullivan is a recurring character in When Calls the Heart, played by Canadian actress Mamie Laverock. Daughter of Patrick and Molly Sullivan, Rosaleen loses her father in a mining accident at the beginning of the series. She is one of the earliest students of the lead character, Elizabeth Thornton (née Thatcher), and leaves Hope Valley for an extended period, only to return and find herself at a crossroads.

When Calls the Heart concluded airing its 12th season on March 23, 2025, on the Hallmark Channel. However, Rosaleen’s appearance has been limited to only seasons 1, 2, and 10 of the show. The eight-year absence allowed her and Laverock to grow from a child to an adult off-screen.

While the show has been renewed for another season, there has been no confirmation on whether Rosaleen's story will be explored further. Created by Michael Landon Jr. and Brian Bird, the Western period drama based on Janette Oke’s Canadian West book series primarily follows Elizabeth, a young teacher from the big city who gains employment in a small community in the Canadian frontier and adjusts to a new lifestyle.

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When Calls the Heart provided Mamie Laverock her breakthrough role

Born in July 2004, Mamie Laverock made her professional acting debut as a child actress in the 2012 film This Means War, starring Reese Witherspoon, Chris Pine, and Tom Hardy. In 2014, she joined the cast of When Calls the Heart in the recurring role of Rosaleen Sullivan, appearing in the first two seasons.

Laverock took her time between projects, appearing in the Hallmark film Wedding of Dreams in 2018 and in two episodes of the Netflix series A Series of Unfortunate Events the following year. In 2023, Laverock returned to When Calls the Heart as a guest star, which marked her final on-screen appearance as of publication on screen.

Tragedy struck Laverock in 2024 when she was hospitalized for a medical emergency and then fell five stories from the balcony walkway of the hospital itself. The 20-year-old found herself in intensive care, with her family opening a GoFundMe page for support. By October 2024, Laverock recovered and shared an update of her getting together with When Calls the Heart cast members at Hallmark's Hearties Family Reunion event.

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Who is Rosaleen Sullivan in When Calls the Heart?

Mamie Laverock’s character of Rosaleen Sullivan is introduced to audiences in When Calls the Heart season 1 as the daughter of mine worker Patrick Sullivan, who soon dies in a mining accident. A young Rosaleen considers mine manager Henry Gowen responsible for her father's death, and holds a grudge against him till she is in her twenties.

After studying with Elizabeth for two years, Rosaleen leaves Hope Valley to return as an adult eight years later. At the time, she is seen working as a nanny for a family at Cape Fullerton. Wanting to train as a nurse, Rosaleen spends her time at the local infirmary. However, she gets infuriated when she comes across Gowen.

On the other hand, Gowen has been haunted by the accident that took place under his watch years ago. He decides to help Rosaleen pursue her career of choice and sets up an anonymous scholarship for the students of Hope Valley to fund her studies.

Rosaleen finds out about her benefactor and refuses to accept the money. However, she realizes that he has changed for the better over the years and ultimately forgives him. Rosaleen and Gowen sit together in the church during the choir performance. She also decides to accept his scholarship and enrolls herself in nursing school, away from Hope Valley.

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