I doubt it will stay a topic she doesn't talk about for long. No doubt once Erin's back / neck is corrected (I'm assuming that they are waiting to do surgery based on the hospital appointments and physio stuff she has posted about) we will have weeks of content centered around Erin's recovery.
I never used to see the favouritism with Emma when I was a blind follower, but it's so blatantly obvious! I think she actually had post-natal depression after having Ethan and has never bonded with him the same way she did Erin, and still possibly resents him hence why he never seems to get any interaction (except for the co-sleeping, because that's clearly spending time with him in bab's world!)