Kathleen L. Ostrum; 1938-2026

Kathleen L. (Pelton) Ostrum passed away on Sept. 12, 2026, at Morning Star Assisted Living with her family by her side.

Kathleen was born Dec. 30, 1938, to George and Forestine Pelton and began her life on the family ranch along the West Rosebud River. Ranch life and hard work were part of Kathleen’s story from the very beginning. As a young girl, she milked cows, tended chickens, fed bucket calves, and learned early the value of hard work and caring for the animals and land entrusted to her.

Kathleen attended West Rosebud School through the sixth grade. She later attended Fishtail School and graduated from Absarokee High School. As a teenager she spent summers cooking for guests, cowboys and family at the TO Bar Ranch near Roscoe for the Branger family.

On Aug. 18, 1958, Kathleen married Richard Merrill Ostrum, beginning a marriage and partnership that would span 68 years. Together, Kathleen and Merrill built a life centered around faith, family, ranching and livestock. They raised Angus cattle, Quarter Horses and, perhaps closest to Kathleen’s heart, Suffolk sheep.

Kathleen and Merrill welcomed their daughter, Venessa, in 1959 and their son, Terrill, in 1961. She was a devoted mother who poured herself into the lives of her children, supporting them through school, sports, horse shows, rodeos and the countless miles and memories.

In 1961, Kathleen purchased her first Suffolk ewes, beginning a lifelong passion. Her flock grew to become an important part of her life, and alongside longtime friend Mary Donohoe, Kathleen and Merrill traveled throughout the region to sheep shows and sales. Together, Kathleen, Merrill and Mary established the D & O Ram Sale, an annual tradition that continued for more than 50 years.

Kathleen was also known for feeding and caring for people. Whether it was family, hired men, ranch crews or guests at the ranch, there was always food to be made and someone to be welcomed around her table.

Throughout Kathleen’s life, her strength was deeply rooted in her faith in the Lord. She was a strong and determined woman, but the foundation beneath that strength was her trust in God. She did not simply speak of her faith; she lived it through the way she served, cared for others, loved her family and gave of herself.

Kathleen is survived by her daughter, Venessa (Ken) Monson; son, Terrill Ostrum; grandchildren, Brande (Clayton) Young, Dustin (Nikki) Ostrum and Jenessa (Adam) Sawyer; great-grandchildren, Caitlin (Tyler) Fowler, Keara Young, Tysen Young, Preston and Stetson Ostrum, and Augustus and Truett Sawyer; sister, Sara (Steve) Kerr; and many nieces, nephews, extended family members and friends. Her husband, Richard, survived her for just 17 days before his passing. She was preceded in death by her parents, George and Forestine Pelton; and her brothers, Merrill and Bill Pelton. Her husband, Richard, survived her by just 17 days.

Kathleen’s family would like to extend their heartfelt thanks to the staff at Morning Star and to the extended caregivers who lovingly cared for Kathleen throughout the last six months.