Catharina "Renie" Nieuwkoop

Catharina “Renie” Nieuwkoop age 97 of Sioux Center, Iowa died Thursday, April 2, 2026, at UnityPoint Medical Center in Sioux City, Iowa.

A funeral service will take place at 10:30 AM Friday, April 10, 2026 at the Centerpoint Church, in Sioux Center, with the Rev. Roger Voskuil officiating.

Visitation will be one hour prior to the services in the church on Friday.

Catharina Braaksma was born February 17, 1929, to Pieter and Gerdina (Pegels) Braaksma in Den Haag (the Hague), Netherlands. She was 11 years old when the Nazis began their occupation of the Netherlands in May of 1940 and 16 when the country was liberated by the Allies. After the war, she attended nursing school and then worked in the neurology ward at the university hospital in Leiden.

She married Pieter Jacobus Nieuwkoop on June 11, 1952, in Den Haag. They immigrated to the United States in December 1952. They first farmed by Ireton, Iowa, and later bought a farm near Carmel. She was a stay-at-home mother until her children were older, and she returned to nursing and worked for Sioux County Home Health for many years. She took great joy in caring for patients again.

She was a member of First Reformed Church of Sioux Center, an active participant in the Lydia Circle for Ladies Aid, sang in the choir, and taught Sunday school. Renie was an avid gardener, and also loved baking her famous butter cookies and delivering them to many friends and neighbors. She also canned and froze hundreds of pints/quarts of apple sauce every year much to the delight of her 17 grandchildren.

In her “golden” years, she volunteered as a kindergarten grandma at Kinsey Elementary. She also many times shared the stories of her youth growing up under Nazi control, her neighborhood being bombed, and the 1944-1945 Hunger Winter that the Dutch suffered through.

Survivors include four sons, Peter W. and Glenda (Punt) Nieuwkoop of Sioux City, Gary and Trudie (Vlot) Nieuwkoop of Chowchilla, California, Terry and Cheryl (Meerdink) Nieuwkoop of Bakersfield, California, and Jack and Julie (Abbott) Nieuwkoop of Manito, Illinois; two daughters, Nancy and Jeff Guenther of West Point, Nebraska, and Tammy and Steve Noble of Sioux City, Iowa; 17 grandchildren; 22 great-grandchildren; 1 great-great grandson; and a sister-in-law, Alice Braaksma of Veenendaal, Netherlands.

She was preceded in death by her husband Pete; an infant daugher Cathy Nieuwkoop; her parents; sister Neep Dekkers; brother Tjip Braaksma; 3 brothers-in-law, Cees Dekkers, John Vande Hoef, and Jacobus Nieuwkoop; and 2 sisters-in law, Alie Vande Hoef and Annie Nieuwkoop.