Stephanie,

With the generations you have mentioned there are no Manx Parish connections. But there must be earlier ones due the Manx surname, I checked all my Kneen data as previous stated on present known and the result was negative. But I did find one entry for Len's find and that was the marriage of Thomas Kneen and Mary Potter on the 3 November 1823 at St Thomas's in Liverpool ,if you want to check the IGI film number 1068943 ( 1821 - 1843 ) it might show more info:

Good luck ...... Brian Kneen