Good then you should take their word for it on their decent relationships with the Mormons. The Lakota generally got along well with Mormons who were the first Anglo group to settle in the Dakotas at the French Ft. Vermillion in 1845. Ponca also got along with the Mormons and saved the lives of hundreds of Mormons who were forced out of their homes in winter.
In the spring of 1847, the Ponca company was called back to Winter Quarters to be with the main body of the Church but most did survive the hard winter thanks to the aid of the Ponca Indians. The majority of these went on to Utah with the group led by Brigham Young. Many became leaders in the Mormon settlements in the West.
In 2003, there was an award instigated by officials of the Sioux Falls, South Dakota Stake which was approved by Church headquarters in Salt Lake City, Utah to belatedly honor the Ponca Indians for rescuing this group of Mormon pioneers in the midst of their difficulties. Members of the sister Stake of Sioux City, Iowa, within whose boundaries the Ponca reservation actually resides, were also invited to attend the event.
The LDS dignitaries presenting the award traveled to the Ponca Pow Wow at their headquarters on the Niobrara to present the commemorative plaque. The tribe was credited with saving the lives of 400 Mormons during the winter of 1846-1847.