In my personal opinion...
This doesn't make sense to me since the mother has no mention/source/hint regarding her (specifically) being in Ireland at all. That's where the hang up is.
Also, Esther's mother and father were married in the USA and appears that they remained together in the USA afterwards.
I did notice that you had imported the GEDCOM file from Ancestry and I had seen a little hint within Esther's bio (regarding the import) that states "... Family Tree files submitted by Ancestry members... " that prompted me to take a little adventure on Ancestry myself. What I had found was amazing and way too common of a mistake so many other individuals make within Ancestry.
I noticed so many Family Trees with the same information as reflected on Esther and I must have looked at just over a dozen of them and had not found 1 "Actual Source". All I found was merged information that's seen as within the Sources tab listing 1 (or more) items stating "Ancestry Family Trees".
I had taken a quick look at many of those and all I found was the same thing regarding their information was based upon other family trees.
So I had performed searches using slight variations and came to a personal ("Opinion Based") conclusion...
I see 2 possible scenarios here. Either Esther was born in Ireland with a different mother and the same father who (for whatever reason) had came to America and married the individual currently listed as her mother OR Esther's mother and/or father is just not correct.
Just a little advice from myself... I always remember that when I'm using Ancestry, I never import/merge another individuals tree because of 2 big reasons. 1) If they made any mistakes (minor or major), those said mistakes will then be imported/merged with my tree that I may/may not be aware of. 2) If they are lacking Source, it makes it that much more work to go through the whole tree I had imported to source up the information that may not be correct if there's mistakes made.
Anyways, I hope that I had explained the above information okay via text... LOL! :-)
I'm really not knocking, debating, arguing, etc... just providing some feedback, advice, opinions, etc... as to the possibility of why your experiencing the "Brick Wall" affect.
I do wish you the best of luck with your contribution to the One World Tree here.