Setting aside the fact that my grandmother let me watch this horror movie as an 8 year old in the late 90s…I’m trying to find what it was called. It was probably from the 70-80s and the plot involved a group of teens/young adults canoeing to this shore (idk if it was an island or puget sound environment) and they find a family living there. The family are hillbilly types and their “kids” are grown adults, but they act like children. The son is probably 30-40 and still gets “switches” from his dad and the daughter had a kid with her brother or father, it died, but she still keeps it in a crib mummified. They end up trying to kill the visitors before they try to leave the area.
I’ve search everything I can and I’ve been trying to recall the movie for over a decade. Please help!