I wouldn't stress too much MG, Zander has only just started crying tears this week at 27 months & not really all that much either. We stressed about it at 6 months, then 12 months, then 18 months before being told it was normal, for him. He produces tears otherwise he'd have conjunctivitis all the time from the eyeball being too dry. So for Zander it's a case of the tears being there, just not coming out when he cries.

Maybe only one of Abbey's ducts have opened so far & the other just has to catch up? Though if you are worried about it, get her checked out by a Dr JIC.