Trivia: George Lutz denounced this remake, stating that it was complete drivel.
Trivia: During filming of the movie, strange supernatural occurrences happened on set. A lifeless body washed up on the shore by the lakeside movie set and actor Ryan Reynolds stated that many cast and crew began waking up at 3:15 a.m. This is the same time the Defeo murders occurred.
Trivia: Ryan Reynolds chose to keep away from Jesse, Jimmy and Chloe so that when his character's personality started changing, it would be easy for him to transition into George's physical and verbal abuse. Ryan's distance from the three young actors made them think Ryan didn't like them.
Answer: He sees the balloon, and instantly assumes his step-daughter is inside the boat house, and hence is in danger of slipping and drowning (or perhaps already in such a situation). He rushes straight out to get there as quickly as possible. Checking her room, or telling his wife would take up time, not to mention he is probably running on adrenaline.