In the Similar Movie category they should list "Leave No Trace"

Leave No Trace

This powerful drama is their story. In the opening moments of “Leave No Trace,” we watch as a man and his 13-year-old daughter wordlessly go about their lives as squatters in the middle of Forest Park, a 5,200-acre tract of public woods just west of downtown Portland, Ore.

The plot follows a military veteran father with post-traumatic stress disorder (Ben Foster) who lives in the forest with his young daughter (Thomasin McKenzie). The novel is based on a true story.[4] It premiered at the 2018 Sundance Film Festival, and was theatrically released by Bleecker Street in the United States, on June 29, 2018.

Will, an Iraq War veteran suffering from PTSD, lives with his 13-year-old daughter, Tom, in the old growth Forest Park near Portland, Oregon. They live in isolation, using forest survival skills and only entering the town occasionally for food and supplies. Will makes their money by selling his VA-issued painkillers to other veterans.

Wikipedia entry:
https://en.wikipedia.org/wiki/Leave_No_Trace_(film)


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Another similarly themed, but not exactly was the 1969 movie "My Side Of The Mountain". I loved this movie as a kid, it was very cool and empowering for a young boy.

My Side of the Mountain is a middle grade adventure novel written and illustrated by American writer Jean Craighead George published by E. P. Dutton in 1959.[1] It features a boy who learns courage, independence, and the need for companionship while attempting to live in the Catskill Mountains of New York State. In 1960, it was one of three Newbery Medal Honor Books (runners-up)[2] and in 1969 it was loosely adapted as a film of the same name. George continued the story in print, decades later.

Sam Gribley is a 12-year-old boy who intensely dislikes living in his parents' cramped New York City apartment with his eight brothers and sisters. He decides to run away to his great-grandfather's abandoned farm in the Catskill Mountains to live in the wilderness. The novel begins in the middle of Sam's story, with Sam huddled in his treehouse home in the forest during a severe blizzard. Frightful, Sam's pet peregrine falcon, and The Baron, a weasel, share the home with him. In a flashback, Sam reminisces about how he came to be there.

Wikipedia entry:
https://en.wikipedia.org/wiki/My_Side_of_the_Mountain