John married Barbara McDougall in Moncton in 1868. The family moved to Maine, where in 1883, John tried to marry another woman, Katie Dempsey.
Deputy Sherif Henry A. Appleton yesterday went to Oldtown, Maine and accompanied by Deputy Sheriff Stafford, arrested at West Great Works one John L. Gillis. It is claimed that some years ago, he married at Richibucto (Kent Co.) N.B/., Barbara E. McDOUGALL and has five children. About a month since he was married to Kate DEMPSEY - 'Bangor Whig' (see original)
Daniel F. Johnson : Volume 59 Number 622
Date June 21 1883
Place Saint John, Newspaper The Daily Telegraph
(another transcription says his wife was Rebecca McDougall)
Name: J. L. Gillis
Birth Date: 1851
Age: 32
Spouse's Name: Katie Dempsey
Spouse's Birth Date: 1862
Spouse's Age: 21
Event Date: 29 Mar 1883
Event Place: Old Town, Penobscot, Maine
Father's Name: Malcolm
Mother's Name: Rachel
Spouse's Father's Name: Patrick
Indexing Project (Batch) Number: I00876-0 , System Origin: Maine-EASy , GS Film number: 11721
Citing this Record "Maine, Marriages, 1771-1907," index, FamilySearch (https://familysearch.org/pal:/MM9.1.1/F46M-LRG : accessed 22 Sep 2014), J. L. Gillis and Katie Dempsey, 29 Mar 1883; citing Old Town, Penobscot, Maine, reference ; FHL microfilm 11721.
He returned to his wife, and in 1900 they were living in Malden. He was survived by his wife and seven children: Mrs. Hannah Taylor, Ada, William, Charles, Thomas, James, Albert.