Hi again Dennis!
They say one picture is worth more than a thousand words so here is Carl and Erik's birth record with the three names clearly being spelled with an e not a. I made notice of the spelling you had posted so I made a point of looking at the spelling in several HFLs and their surname was spelled with a e.
I just looked in the files at SVAR (Riksarkivet) Folkräkning 1890 (Västmanlands län) and here is part of the information for Erik Reinhold's family:
Fam. nr 1
Erik Reinh. Hellström, f. 1849 i V. Barkarö, Statkarl
Karolina Dalfors, f. 1837 i Ryttern
Amalia Ottilia, f. 1879 i Berg
Arvid Anshelm, f. 1882 i Kolbäck
Amanda Lovisa, f. 1871 i Ryttern
Note the spelling is Hellström, not Hallström.
Where did you get the spelling Hallström?
Let me know if I can be of more help.
Hope this helps!
Have a nice day!
Don