The one-page letter from Thomas Sears to Wiley Kear merely stated that he thought his family's name was originally Cears. Wiley's reply is posted at
http://johnkear.fortunecity.net/wiley/wiley0401a.html. I probably should also post the Thomas Sears letter that I found at the Maryland Historical Society.
BTW, I found this board the same way you did, by searching on Google for cears.