I am not related, but do have her in my tree as Christina Poulsen. She's in my tree because her son, Ephraim, married into my Kidman family.
After Peter died, she moved to Idaho. She and her children used the Yergenson spelling in Idaho.
Today I found her obituary from 1913, and thought you might like to see it. Her obituary says she was born in Orehouse, Denmark - googling Orehouse Denmark shows only one other reference, but nothing about its location in the 1800s/early 1900s.
Here is her page in my tree (which is temporarily a public tree):http://trees.ancestry.com/tree/5806682/person/-484205863