How old was Aho when she attended the last Kiowa sun dance?

The last full Kiowa sun dance took place in 1887. As Aho, Momaday's grandmother, was born in 1880, that would make her six or seven years old when she participated in the dance. She also watched the last ever sun dance—this time incomplete—three years later, when she was ten years old.
The Kiowa were unable to complete that year's sun dance because they were interrupted right in the middle of this ancient ritual by a detachment of soldiers from Fort Sill. The soldiers had orders to disperse the Kiowa tribe, even if it means that they will not be able to complete the sun dance. This fateful day—July 20th, 1890—is the formal date of the tribe's surrender, and ten-year-old Aho is a witness to the most tragic event in Kiowa history.