Theresa Grosvenor

Theresa Marie Hanson Grosvenor joined heaven on February 4, 2026, after nearly six years of courageously battling terminal cancer.

Born on October 20, 1963, in Las Vegas, Nevada, Theresa grew up in Elk Point, South Dakota, and was a proud graduate of the University of South Dakota. She later found her true home in the Iowa Great Lakes, where she became an Okoboji lover and an Arnolds Park superhero to all who knew her.

From 1996 to 2001, Theresa was the heart and sparkplug of Arnolds Park Amusement Park and the Lakes Area community, bringing unmatched energy, joy, and connection wherever she went. She remained deeply involved in the community for many years beyond, always cheering people on, lifting them up, and staying connected through social media, prayer, and constant positive vibes.

Theresa also took great pride in her work as the manager of Manhattan Beach Resort, where she treated every guest as if they were family. She poured her heart into the resort, forming lasting connections with those who stayed there and taking genuine joy in creating a welcoming, home-away-from-home experience for all.

Music was a constant companion in Theresa’s life. She loved her classic rock hits and could almost always be found listening to her vintage radio—complete with the cassette tapes she still proudly used—letting music fill her space with the same energy and warmth she brought to everyone around her.

A true hippie at heart, Theresa’s greatest desire was to bring happiness, love, and light into everything she did. Her family and friends meant the world to her, and she never stopped showing up for them in the ways that mattered most.

Theresa was a devout member of Calvary United Methodist Church in Arnolds Park. She remained deeply connected to Christ throughout every season of life, living her faith through love, kindness, and the joy she shared with others. She is now at peace, reunited with Him forever.

Theresa was preceded in death by her beloved mother, Barbara Hanson, and father Douglas Stowe, both of whom she held close in her heart.

She is survived by her children, Hannah Grosvenor (Tyler Pauley) of Tampa, Florida, and Calvin Grosvenor of Okoboji, Iowa.

She is also survived by her siblings: Mike Brock (Lisa) of Michigan, Debra Martucci (Joe) of New Jersey, and Denise Long (Chuck) of South Dakota.

Theresa leaves behind many cherished nieces and nephews: Jeremy Chicoine (Valerie), Cory Chicoine, Dan Chicoine, Annie Long, Maggie Anaya (Knick), Charlie Long, and Carlie Long, along with countless friends whose lives were brighter because of her.

Theresa lived boldly, loved fiercely, and did everything on her own terms. Her spirit, laughter, and light will continue to ripple through the lives of all who were lucky enough to know her.

A Celebration of Life will be held in the Okoboji area on Friday August 7, 2026. More information will be shared at a later date.