I was talking with a Danish guy, he is 24. He said he and his brothers saw, when he was 4 or 5 years old (2000s) a movie with a blonde kid and he thinks his friend (he does not know if they were related) who was an old man and who looked like Ernest Hemingway.
Apparently in the movie there were aliens, and the old man had to face the decision whether to stay or go with the aliens.
It was not a comedy, it was a drama possibly. And he thinks that maybe it is American from the 80s, that you never actually see the aliens, and the old man says "shut up!" a lot, but that may be his 4 year old blurry memory.
I thought maybe Cocoon, which has lots of old men, but it does not fit the blonde boy description.