Book dilemma

My oldest son, Tommy, has always liked books, but he has tended strongly to the nonfiction section. Animals, dinosaurs, weather, planets, composers, presidents... my 9-year-old gone through all those phases. And that's great, of course. Except that he really needs to work on his reading comprehension skills, and because he is mildly autistic, he also can struggle to interpret subtleties such as expressions and emotions.

In other words, it would be very good for him to read some fiction, too.

His 6-year-old brother has been easy: he'll read any story that involves animals and sports, even if it has chapters and stretches his abilities. We've had some successes with Tommy in the past; he loves Amelia Bedelia, the daffy maid, and the Berenstain Bears and SpongeBob. Still, I wanted to get him into something longer, with chapters. We tried Magic Tree House, Junie B. Jones and Encyclopedia Brown with limited success. He likes the Ramona and Fudge series, but he seems to like them better when I read them to him. 

Then he struck what he considers fiction gold: The Diary of a Wimpy Kid books, and just today, the Captain Underpants series. 

Not surprisingly given my son's penchant for potty humor, these books are filled with semi-off-color jokes and stories. Nothing X-rated at all, but plenty of references to toilets and farting and buttheads and darn stupid bullies. I can understand why he likes them; they can be very funny, they have good characters and they appeal squarely to many boys' sense of humor and emotional struggles. A lot of his friends are big fans, too.  

But I'm a little torn. We already have problems with Tommy and his brother making inappropriate comments and jokes, especially at the dinner table and even sometimes in public. Should I really be letting him read books that encourage this type of behavior and humor?

For now, I'm saying yes. Tommy is now curling up with a book in his bed and begging to stay up late to finish chapters. He'll show me all his favorite parts and wants to talk about what they mean. To me, that's worth putting up with a few more comments about farts than I might have otherwise. And I'm hoping this experience with books will encourage him to dive into more substantial chapter fiction books.

Now I see there's a Diary of a A Wimpy Kid movie coming out. Somehow I have a feeling we're going to be in the audience.