He was listed simply as John Miller when he married Rebecca in 1846.
They settled in Tuscarawas county and are listed in 1850 as John M. Miller (26, PA), wife Rebecca A. (22, OH) and daughter Nancy (2, OH).
Listed as John M. Miller (34, PA), a farmer, with wife Rebecca A. (32, OH), 3 daughters and a son in 1860.
1870 census lists John M. Miller (46, PA), Rebeca A. (42, OH) with 4 daughters and 3 sons.
In 1880 John M. Miller (56, PA) is listed with his wife Rebecca (52, OH) and 2 sons, 3 daughters and 2 grandchildren.
He is listed in 1900 as John Mot Miller, a farmer (76, GER) married 53 yrs, with 5 of their 10 children still living. With his wife Rebecca A. (Nov 1827, OH) and son Uber W. (Jun 1867, OH).
His headstone and obituary seem to be the only records which reference his Mot Miller name (middle and last or split last name).

This hand-typed obit on the death of John Motmiller (1823-1901) was among some memorabilia left by Mott O. Miller (1928-1984).
Death of John Mot Miller
A copy of the Uhrichsville (OH) Chronicle contains notice of the death of John Mot Miller, a brother of William Mot Miller and Mrs, Benjamin Parrish, who formerly resided near Martinsburg, but who died several years ago. The notice speaks in the highest terms of John Mot Miller, and the following is a historical sketch of the family;
There was a singular episode in the life of Mr. Mot Miller's father, George Mot Miller, who was born in the Grand Duchy of Baden, Germany, in 1776. He was 41 years old when he and his wife and four children sailed for America. Their ship was wrecked, and they were rescued off the Madeira Islands, where they stayed for a year. Then they came to America, and were sold to pay for their passage. One of the children died on the way over, and was thrown overboard, because, as they believed, whales were following the vessel. But burials at sea were common enough in those days of slow transportation, and they were evidently mistaken as to the reason for casting their child overboard. They were on the ocean for three or four months,
When he had served his time and thus paid back the expense of his passage, his master gave him a horse, saddle and bridle, as used to be done in the case of a bound boy who had reached the age of freedom —21 years. George dropped dead one Sunday morning on his way to church, and he is buried in West Union cemetery, where his son finds a last resting place. He was small in stature, being only five feet two inches in height, but was a very powerful man, as was also his son, John, who in his prime never met his match in physical strength.