Omfg! What an idiot!
Whit that going on if I was you and my eldest showed even a slightest hint of understanding what's happening (which by the way I'm 100% sure he/she already does) I would say something immediately. You can just tell H that the eldest asked or seemed confused.
I spent 3 months anxious every day about telling them (new me would have asked W once).
It isnt that big of a deal. NOT telling them while they may understand or are confused, is worse IMO.


Me: 34
Stbxw: 30
D:5 D:3
Mini bd: May/June 2019
Married: Aug 2019
BD: 6th Dec 2019
OM Confirmed: Feb 2020
March 2020: I filed for D
Waiting for D to be finalized and W to move out end of January 2021