I don't know where "Power County, Idaho, USA" comes into this.
Helen MacDonald came from Scotland, lived in Wales for a while and went to Sussex as did her parents and siblings. Somewhere between 1897 (when Helen was 21)and when she married Aleck in 1917 she was married to a gentleman by the name of Power (I don't know his first name or anything about him)and he died. (Helen said she was a widow on her 2nd marriage certificate)
I have tracked some posibilites which I have put on the tree for now but may alter them is I can find some more substantial info. The is a trip - Argentina, River Plate to Southampton with a Mrs Power and Mr J Power. I have then found a James Power on the census living not far from Helen in Sussex who died abt 1907. I can't prove its the ones I am looking for and rather doubtful.