Need explantation

chris, I know it's been over a year since you've posted this, but no one's replied and I just re-watched this movie recently, so I'll give it a try anyway whether you read this or not...

Kurt (posing as Gary) was never in the daughter's room at the end. He's been on the side of the road the entire time. All the scenes with the people in the softball photo was all in Kurt's mind.

But if you're talking about the boy in bed at the very end during the credits, that's not Kurt. It's assumed that Pat had another son with his new wife.