I like those ideas! Maybe their mothers were best friends from the same village and knew each other before Penelope's mom died, and Crow's mom was just too sad about it to ever bring her up in conversation with him. He would have been really young when she passed, so he wouldn't remember her anyways.

Also, maybe their fathers know each other too, since both mothers ended up with noblemen?
I don't think Penelope's dad would like crow's very much though because he's as stereotypically proud as a noble can get. They could still have met before at least.

Ooh, maybe they were both passing through the village at the same time, except Crow's father just got Madeleine (that's Crow's mom's name, which hasn't been revealed IC yet) pregnant and bailed, but Penelope's father came back because he loved her mom, and she didn't get pregnant until later in their relationship?

I dunno if you've already thought up a story for her parents, but it would be kinda cool if Crow and Penelope's histories were that tangled up.