Continuity mistake: Just after Inga walks out of the main house after first looking at Mark, he turns around to look outside towards her. His left hand is at his side when he turns, but in the next shot, his hand is suddenly touching the back of his trousers. (00:55:05)
Continuity mistake: When Pelle gets his phone to show Dani photos of his commune, Dani stands up from the chair she is sitting on with both her hands at her side. The camera changes to a different angle where she moves over to Pelle's couch and both her hands are more closed together. (00:23:15)
Continuity mistake: When Christian is at the cafe with his friends, just after the waitress takes the tip and Pelle tells him "don't forget about all the Swedish women you can impregnate in June", Christian raises his hands in the air. The shot then cuts to Mark and Christian's hands are suddenly lowered. (00:08:05)
Continuity mistake: Just after Dani re-reads the worrying email from her sister, she takes out her phone and holds it with both hands near the bottom. We are then shown a close-up of the phone and her right hand is now nearer to the top. (00:03:15)
Other mistake: In the end credits, the cast is listed as "in order of appearance", but the cast are merely credited in no particular order. (02:47:55)
Continuity mistake: When Ingemar is watching Christian's body get engulfed by the fire, he is holding his hands together, with his fingers interlocked with each other in a slightly curved position. The shot then cuts to a different angle where his fingers are more bent. (02:43:20)
Continuity mistake: When the female Hårgas are consoling Dani after she sees Christian having sex with Maja and they begin crying in unison, Dani's hair is tied back, but when it cuts to a different angle, a few strands of hair are suddenly hanging over the side of her head. (02:27:55)
Continuity mistake: After the male elder jumps off the cliff, there is a string used to tie his collar shown on his clothes when he is on the ground. The string is on the right side of his chest when he lands, but when his head gets smashed with a mallet seconds later, the string is on the left side of his chest. (01:11:40 - 01:12:35)
Continuity mistake: When Dani is looking at the photos of the commune, as Pelle says "we make those clothes special for every winter and summer solstice", he is holding the phone and begins to bend his thumb. In the next shot, his thumb is straightened with no bend. (00:23:30)
Answer: It's actually a boy named Ruben. It's alluded to him being disfigured due to being the product of incest. In the context of the movie, Ruben is supposed to be an "oracle" who comes up with sacred scriptures, runes, etc. From what I understand, due to his deformities and cognitive disabilities, he's considered to be less "constrained" by typical mental/emotional limitations, and thus more open-minded spiritually. (Basically, they believe that because he's so simple-minded and childlike, he's open-minded enough to able to communicate with higher powers).
TedStixon