I have done a lot of research on Isle of Man families over the yrs. The following is a good resume of your Thomas.
Thomas Cottier 1829 - 1899
Farmer and Stock Raiser
Born: 3rd February 1829, Bride
Died: 19th December 1899, Holt County, Missouri
Father: John Cottier (1784-1847 Ballacottier Bride)
Mother: Catherine (nee Callow) 1802 Maughold-24 Dec 1897 Holt Co Missouri
Married: Minerva Beeler, 7th February 1850, Holt County, Missouri
Children: They had eight children, seven of whom are
Hannah J., John T., James C., Lizzie, Mary S., Emma and Robert.

Thomas Cottier was among the early pioneers of North-Western Missouri. He
was born at Bride on 3rd February 1829, his parents being John and Catherine Callow (William Callow/Catherine Kelly)Cottier.
He spent his boyhood working on the family farm receiving fair educational
advantages. At eighteen he emigrated to America crossing the Atlantic in
February 1847 and after a nine weeks' voyage he landed at New Orleans from
where he went by steamboat to St. Louis. He then went to Western Missouri
and from there by team to Holt County.
Soon after arriving in Holt County he became engaged in teaming in Oregon
and also for the government on the plains during the Mexican War. His mother
came out to join him in 1849.
On the 7th February 1850 Thomas married Miss Minerva Beeler, a daughter of
one of the early settlers of Holt County. She was a native of Indiana, who
had come to Missouri with her mother's family in 1844.
Thomas and his wife went to live on a farm which he had pre-empted in 1847
and after that he concentrated on farming. At the time he owned a yoke of
oxen and one horse. The cattle were used to break the ground and the horse
to tread the corn. From this lowly beginning he eventually owned one
thousand acres of fine land in Holt County and some two hundred acres in
Nebraska. The home farm contained 270 acres, had a fine residence and 'an
excellent orchard twelve acres in extent of 600 bearing trees, two peach
orchards and a large amount of small fruit'. His farm was one of the finest
in the county. He also had an excellent stock farm in Liberty Township.
During the Civil War Thomas Cottier served in the Enrolled Missouri
Militia, whose duty it was to defend the property of the citizens. Although
no office seeker ' . . . he filled the district offices for several terms'.
He and his wife were active members of the Christian Church and they had
eight children born between 1852 and 1864.
Victor Kneale

Source: History of Holt and Atchison Counties, Missouri, published 1882 by
the National Historical Company, St. Joseph, Missouri p.364-365.

Hope this helps. My notes say he was born in Ramsey 3 Feb and baptized in Bride 4 Feb.

Donna Douglass
Gig Harbor WA USA