The following text is from a book that Bob Kosters,Willem's Grandson wrote:

Gerrit Willem Kosters came to America when a boy of seven years, with his
parents and brother Hendrik Jan(Heine), age 15, Aleida, age 12, and Jan age4.
He traveled with the family to Michigan, Virginia, New Jersey and at last to
the homestead in Iowa. He was exactly eleven years old when the family
homesteaded and had some hard years in Iowa. After ten years he started over
when he moved to Dakota Territory to homestead when he turned 21. A stake in
the ground where Harrison would some day be located was where the Dakota
Homesteaders were headed. To get there, most of the homesteaders took the
train from Iowa to the end of the track at Plankinton. There they would unload
whatever goods they had, and traveled about 30 miles south to the land office
run by Frank LeCocq. As Gerrit Willem was one of the first groups to arrive in
1882 he homesteaded 167 1/2 acres just south of Joubert. The property was lots
3 and 4 and the south half of the Northwest quarter of section 4, Clark
township. On April 21, 1890 he paid $4.00 which was the balance of payment for
his homestead, and filed at Yankton. The village of Joubert, just north of the
Kosters homestead, had its beginning in 1882 as did Harrison and New Holland.
The town was first called Emden and later was changed to Joubert. Joubert was
the name of a Dutch General.
Shortly after Gerrit Willem had homesteaded, the Van Zee family left
Herwijen Gelderland, Holland on Sept. 28, 1882 and arrived in Pella, Iowa as
early as 1846. Gerrit and Heiltje Van Zee, with seven children, homesteaded 2
1/2 miles west of New Holland on the south side of the road in the Spring of
1883. The Van Zee's 5th child was a daughter, born April 2, 1867, and they now
lived about a mile from the single homesteader, Gerrit Willem Kosters. New
Holland church records show that Gerrit Willem Kosters and Neiltje (Nell) VanZee were married April 4, 1884.
1900 - Gerrit and family are farming in West Branch County Iowa, down the road from his Father Hendrikus Kosters Farm.
1910 - Gerrit and family are farming in Lincoln Township Iowa.
1915- Gerritt and family are living in Sioux Center.
1920- Widow Neeltje is living in Sioux Center with daughters Alyda,Nellie,Minnie and Margaret.