So... I just finished the scene where we first meet Agatha and... um...
Spoilers and Wild Mass Guessing below:
Is... is Cole actually Marrow AND Hamish's biological kid and not just Marrow's? Because ngl, I was kind of enjoying the whole "you're not my real dad" dynamic Cole had going with Hamish and making him Hamish's biological kid kind of ruins that. It's a fairly cheap way to resolve the conflict in Hamish and Cole's whole sort of "son not liking his step-dad" relationship and opens up a number of rather uncomfortable questions. Like, why wouldn't Marrow and Hamish just TELL Cole this when he was younger? Cole makes no secret of the fact that he thinks of Hamish as "Dad's killjoy boyfriend" instead of "Dad #2" and it makes Marrow out to be a really shitty partner if he didn't step in and clear this matter up for all these years. I just can't see Marrow doing that considering what I've seen of him.
Basically, I hope I'm wrong and just overthinking things. There's clearly something magical about Cole's origins based on what Agnes said, but what is still unknown and I really hope it isn't what I think it is.