When Lucas is speaking with the Swedish man who is desperately trying to find his son, he grabs a pen and starts writing the boy's name with his left hand but in the next shot he is writing with his right hand.
When Henry is first shown after the tsunami hits, his hair is dry and mostly neat. He immediately starts calling for Lucas and Maria, and his hair all of a sudden is very wet.
After the wave subsides, and Maria and Lucas come to rest on a floating log where they catch their breath, a leaf on Maria's left shoulder disappears and reappears a couple of times.
In the hospital, where Thomas and Henry are talking, the ceiling fan at the top left is off. In the next shot, the ceiling fan is on.
While In Hospital Maria's Air Line Is Sometimes Kinked And Sometimes Not.
After the tsunami subsides, as Maria and Lucas are climbing up into the tree, a man briefly appears from behind some branches just above them in the background.
When Daniel meets with his father, he says in Swedish - "vad tung du är Johan (how heavy you are, Johan)" instead of the character's name Daniel. This is because the real name of the character Daniel, is Johan, and it's his real father Jan.