Mary was born in 1815 in Ireland. She appeared on the census in 1870 in Fork Lick District, Webster Co., WV. She appeared on the census in 1880 in Fork Lick District, Webster Co., WV.  John McGuire and Mary had the following children:
 

• Peter J. McGuire was born in 1853/54 in WV. He appeared on the census in 1870 in Fork Lick District, Webster Co., WV. He appeared on the census in 1880 in Fork Lick District, Webster Co., WV.
• Sylvester McGuire was born in 1857 in WV.  He appeared on the census in 1880 in Fork Lick District, Webster Co., WV.
• John McGuire was born in 1857.  He appeared on the census in 1870 in Fork Lick District, Webster Co., WV. (this is probably Sylvester????)