My name is Dan Hansen and I am the family genealogist (so to speak) here in the US.
Christian Arthur Hansen is not a relative that I know of.
And Karsten is not a relative that we know of either. We have been in contact with him but could not find an official link.
I can not confirm that Anna Marie Clark who died in 1943 is Anna Christina (Schmidt) & Hermann Willer Hansen's daughter Anna Marie Hansen(Clark being her married name). But it very well could be. I would just like to first see the death certificate to verify.
Feel free to contact me at StenderupHansen@gmail.com
to discuss further. Our family tree is monstrous and now goes back to the 1400s, so if you are part of a branch I would like to add you to it.