I have the marriage records from Grafton.
Nelson Henry Wood, age 22, res: Sutton, MA Born in Suncook, NH
parents: Nelson Wood and Adella Brough
married 19 Aug 1900 Fisherville (Grafton, MA)
Rosa Nero, age 18, Res: Grafton, MA, Born: Line Mountain, NY
parents: John Nero and Mary David
My guess is that Nelson Wood Sr. was born in New Hampshire and not Lowell, MA. You may want to look at the 1880 Census in New Hampshire.