I could have sworn Ophelia x Kevin, the scenes with Kevin and Brenna / Cath were just his thoughts. Since they were going on as he was talking to Ophelia. I'm pretty sure that was like a "what if" he becomes a part of the family inside of a bad end lol.
Anyways, while going through that scene. I think I may have found how Ophelia is getting pregnant with Sterling.
Kevin asks her wasn't she on the pill and she says she was suppose to be, but apparently not. I'm thinking someone swapped out her birth control pills. Either Hunter for plans to knock her up himself or Cath being Cath and pulling a prank.