The African Queen (1951) - did Charlie and Rosie have sex?

In the original novel they become lovers shortly after successfully fighting the rapids. While the ending of the book is very different from that of the movie, the scenes regarding the rapids are pretty much spot on to the origin novel. On screen, of course, nothing was ever explicitly shown beyond a hug and chaste kiss. However, from the point of the replacement of the bent propeller shaft on, whenever Rose speaks to or looks at Charlie Allnutt, no one could miss the (quite obvious) love in the looks she gave. Katherine Hepburn was magnificent (in my opinion) in this role. She goes from the haughtiness she later displayed towards John Wayne in Rooster Cogburn, to shown sincere love and devotion in a very convincing manner. It appears, to the uninformed, that there was quite a lot of chemistry between she and Humphrey Bogart.

The reality of making the movie itself, however, was much much different. Bogart had taken his young newlywed (Lauren Bacall) along on the trip, going on a quick whirlwind 'honeymoon' trip through Europe on the way to Africa. Once in Africa, during the shooting of the film, things didn't go so smoothly. Everyone except Humphrey Bogart and director John Huston came down with dysentery. Katheryn Hepburn was a 'tee-teetotaler' (didn't drink alcohol), while pretty much everyone else were heavy drinkers. Her sobriety actually caused some minor health issues, as the alcohol (mostly gin) being heavily downed by everyone else, was helping to combat malaria and a few other possible diseases.

This all comes from a combination of the Bogart and African Queen wikipedia pages (linked above), and Hepburn's excellent book and papers I have read on the movie and the making of it.