An excellent film about a father and daughter living off the grid: Leave No Trace

Debra Granik's 2018 film, Leave No Trace (she also co-wrote the screenplay w/ Anne Resellini, basedon the novel My Abandonment, by Peter Rock), is an intense and gripping story start to finish (well, the pace slows quite a bit in the final, near-idyllic act) of a father (Ben Foster) living in a tent on public land w/ his daughter (Thomasin McKenzie) whose probably about 14 years old. He trains her in survival skills and instills in her the attitude that the world is out to crush their souls and they must resist. This motif recalls a # of recent works, such as Educated and My Absolute Darling, though what sets this apart from some of the more ghastly works in this genre is the sympathetic portrayal of the obviously troubled father: Foster cares without question for his daughter, and they have a loving relationship without a hint of sexual perversion or mistreatment - though it's by no means a rosy existence: their life is difficult, and the young girl is starting to feel the need to break free from her dad and to be with others her own age. Over the course of the film they are found and brought into protective services and offered good housing and support - it's a pleasure to see that the there are no cheap shots at the welfare workers, who are humane and who do their best to help both father and daughter, after ascertaining, rightly, that this is not a case of abuse. Just as the daughter - whose character is also named "Thom" - is getting comfortable in new surroundings, the father forces them to pull up stakes and hit the road, which leads to a series of adventures and misadventures and finally to an ambiguous but quite credible denouement. All told, the film is much more humane than other "road" movies - and much more believable as well. I wonder about the source novel - and whether the protagonist was a boy or a girl. Intentionally, I assume, this film gives us virtually no back story; we have no idea how long father and daughter have been off the grid, whether she's ever been in school, in short nothing of their life from her earliest childhood, when her mother died, up to the present, at least 10 years later. The father's life story, as well, is left vague, except for hints that he had a traumatic experience in the Marines, perhaps in the Gulf War? So it's a movie very much in the present tense, a movie sympathetic to all of the characters (except one, a rather tough boss/landlord in their first housing - though he's by no means abusive or exploitative) that keeps us engaged throughout.