Watching Indiana Jones right now, and Marians comments like "I was just a child" and Jones' falling out with her father seem to indicate that Jones fondled a child in the story. Which... uh. What the hell? It's not even like a big part of the plot, it's just thrown in
I did a bit of googling and although I'm sure there are outliers, it looks like most first time marriages were at 21 for women and 24 for men in the 1920s. So, it's definitely creepy for the more than 10 years between the characters of Marion and Indy, even if Hollywood thinks it's normal.