MacNeil was born and raised in Vancouver, British Columbia. She began her acting career at a young age, and appeared in her first significant film production in a non-negligible marginal role. In Mr. Troop Mom with all-rounder George Lopez in 2009 she had the role of the Kayla. The following year the young actress came to her international breakthrough when she was cast in the role months before as "Patty Farrell" in the first film adaptation of the successful book series Diary of a Wimpy Kid. For her performance in the film, the young Canadian was awarded several times and honoured. So she has received many awards in the Young Artist Awards 2011 nominated for a Young Artist Award in the category "Best Performance in a Feature Film - Supporting Young Actress" on 3 August 2012. In addition, it was with the cast of Diary of a Wimpy Kid, consisting ofPeyton List, Karan Brar, Robert Capron, Grayson Russell, Zachary Gordon, and Devon Bostick at the same ceremony with a Young Artist Award in the category "Best Performance in a Feature Film - Young Ensemble Cast". In 2011 MacNeil followed for numerous other appearances, including among other things a guest appearance on the short-lived Canadian police series Shattered. They also took over in 2011 published the second part of the film, ', Again in the role of Patty Farrell and was also still in a guest role in the series '. After these engagements, MacNeil was in the following year again represented at the Young Artist Awards. She received the award of the Young Artist Awards 2012 a nomination in the category "Best Performance in a TV Series - Guest Starring Young Actress 14-16" for her performance in Shattered and was additionally a Young Artist Award in the category "Best Performance in a Feature Film - Supporting Young Actress" for their involvement in Diary of a Wimpy Kid: Rodrick Rules. In 2012, MacNeil had a guest role on RL Stine's The Haunting Hour and made an appearance in an episode of Falling Skies. In 2012, she played a supporting role in Norman Buckley'sdirectorial debut film The Pregnancy Project and returned to ', where she was nominated to the Young Artist Awards 2013 in the categories of "Best Performance in a TV series - Guest Starring Young Actress 14–16" for her performance in American television series "Falling Skies" and "Best Performance in a Feature Film - Supporting Young Actress" for her performance as Patty Farrell in ' and part of the "Best Performance in a Feature Film - Young Ensemble Cast" where the cast won. In 2013, she appeared on Canadian-American horror filmHorns starring Daniel Radcliffe, where she played the role of young Glenna. Furthermore, that same year she appeared on three episodes of the American crime drama The Killing and again on an episode of R. L. Stine's The Haunting Hour: The Series In 2014, MacNeil appeared on several TV series such as Almost Human, Motive, and Strange Empire. As well, she appeared on two TV films, The Unauthorized Saved by the Bell Story and Damaged. She was nominated that same year to the 35th Young Artist Awards in the category of "Best Performance in a TV Series - Guest Starring Young Actress 17-21" for her appearance in R. L. Stine's The Haunting Hour and in the category of "Best Performance in a TV Series - Recurring Young Actress 17-21" for her recurring role in The Killing. She was nominated on 2015 for the 36th Young Artist Awards in the category of "Best Performance in a TV Series - Guest Starring Young Actress 17-21" and the Joey Awards in the category of "Best Actress in a TV Drama Guest Starring Role Age 14-18 Years" for her work on Strange Empire. Outside of acting, MacNeil started to work that same year as a fitness coach in where she continues to work as of 2020. Between 2016 and 2017, she had a recurring role on You Me Her's first 2 seasons as Ava Matherfield, Lori's teenage daughter. In 2016, she appeared on On the Farm, The Edge of Seventeen and The X Files. In 2017, she was nominated for the Canadian Screen Awards in the category of "Best Performance by an Actress in a Featured Supporting Role or Guest Role in a Comedic Series" for her work on You Me Her. In 2019, she appeared on Episode 2, "Noise, Noise, Noise" of the American television series Deadly Class, portraying the role of Rory's daughter.
