I'm sorry I don't think I have any information on Chatburn's in the Chatburn or Darwen areas, do you know they are some miles apart? Whilst I have been researching my Chatburns I have seen Chatburns in the Chatburn area as this is not far from Sabden, but I have not recorded any of this because I have not found a link to Chatburn (the village....this is getting confusing!!)as yet.
As far as my American connection goes...I only have a letter sent from Idaho in the early 1900s, that I believe my great, great, grandmother's brother wrote to his cousin. I'm still looking for the cousin.
I will keep your details, and will let you know if I come across anything that may be of interest to you.