I always liked the Caladrius. Perhaps something where Johnny and Fran have to intervene to save one of them from being harmed/hunted/whatever works for the story. Set after Daniel and before Alice. The encounter is a catalyst for the two of them to move forward in their own healing and start considering another child.

(Bonus: Fran has awful morning sickness the very next day and they're both like 'already?', and then the doctor they see for confirmation (maybe the same Caladrius?) says 'less "already" than "six weeks ago"'). Because Alice will decide when she's ready to be conceived rather than waiting on her parents, thank you very much.)