William Rogers mentioned a sister named Elizabeth Cole. The only Cole baptisms in the Watford registers record children of John Cole, so it is John that Elizabeth is thought to have married.
Further information on the Rogers family and their English background is in "The English Ancestry of the Pilgrim Thomas Rogers
and his wife Alice (Cosford) Rogers", by Clifford Stott, The Genealogist, Vol. 10, No. 2, 1989. (On line at: http://www.richmondancestry.org/thomasrogers.shtml)