Should I tell her or just let is pass?

My SO and I have been ttc for 18 months now and have only told a couple of close friends; we haven’t told either of our families yet.

We have finally been referred to a fertility clinic for further tests and treatment but the waiting list is long so might not be seen for another few months, Anyway...

My SO’s sister tagged me in a post on Facebook of a pregnancy test saying “congratulations it’s another cat”. I do have two cats already, a tattoo of a cat and absolutely love cats.

What I’m really wanting advise on is if I should tell her that I didn’t find it funny because every negative is a step close to getting another cat to fill the void of not getting pregnant or just let is pass as she doesn’t know we’re trying so thought nothing of tagging me in it.