OK, so Eugene sees the Stabbington Brothers in prison and wants to know how they knew about Rapunzel.  When he tells Eugene the old lady told them and Eugene realizes that Blondie's in danger, that would imply that Rapunzel told him about her mother (and her relation to her magic hair, i.e. it keeps her young), yes?

And I'm totally not watching that scene over and over because it's so incredibly guh that he knocks out the guards in a fit of rage because, dude, the Stabbington Brothers messed with his woman.  Or the fact his voice is totally hot.