What is the date of Barbara Folan's emigration? She married in Maine, so was she heading right to Maine from Boston? If so, and the friend/sponsor Barbara Folan was living in Maine, I can probably figure out who she was and maybe make some more connections.
I don't know a lot more, except there were two more children not on the 1911 census - Martin and James.
The children on the 1911 census:
Julia married Thomas Ferrell or Fennell in County Kildare
Bridget married Robert Dickerson
John married Mary Feeney and stayed in Ireland
Mary - no info
Patrick - no info
Barbara married Charles Kemp in Gorham, Maine
Stephen - no more info
Nora - no more info
Martin lived in Canada
James died in 1981 in Vancouver