It was only after Mr. Gold's first (and only) impromptu visit – the one concerning his long-lost son – that Archie began to wonder exactly how much of the dangerous man's reputation could be explained away. It started consuming his thoughts. Mr. Gold's customary coldness – was that a wall? His self-serving deals – perhaps projection of some sort?
Psychologically, Archie was sure, it all made sense. It wasn't until he was lying in bed one night that it occurred to him.
The first time Archie had met Mr. Gold, he'd sworn the other man was wearing a wedding ring. Later, he'd realized he was wrong – while it definitely looked like a wedding band, the ring was on the wrong hand.
In bed that night, though, Archie remembered that widows and widowers wore their rings on the right hand sometimes. And of course, Mr. Gold had to have made that long-lost son with someone.
Inspired by the idea, Archie wracked his brain to think of any rumors involving Mr. Gold's sexual activities (and boy, was that a sentence he never thought he'd think). So far as he knew, the man had never coupled with anyone in Storybrooke. He'd have to bring it up to Ruby in the morning.
I'm on to something, Archie thought. I know it.
And, as an afterthought before he fell asleep, he assured himself that his interest in Mr. Gold's sex life was purely from a medical point of view.