In the scene where Thomas (Jared Padalecki) is crying, Peter O'Toole had to reel him in after the take because Jared couldn't stop crying. He told him, "Stop that. These are Thomas's tears, not Jared's."
Jared Padalecki is so muscular that he was going to try and lose weight in order to look more like Thomas Kinkade, but filmmakers decided that he should remain at his weight of 220 pounds, because they thought that his strong, muscular image gave him a much more approachable and friendlier appearance.
Thomas Kinkade is left-handed but Jared Padalecki is right-handed. To prepare for the part, Jared only used his left hand for the month leading up to filming. There was also a left-handed artist on set who helped Jared look more natural as he worked.
Aaron Ashmore, who plays the younger brother of Jared Padalecki's character, is in fact three years older than Padalecki. Ashmore was born in 1979 while Padalecki was born in 1982.
Glen listens to Claude Debussy's "Clair de Lune" a few times, which is not listed among music used in the film.