Placed on the cushion where the head of the Infanta Sancha lay was found a letter, dated December 22, 1868, which explained: "In the year 1868, during the reign of Doña Isabel II, the Pantheon of the Kings was found in a completely abandoned state, and the body of the queen Doña Sancha, perfectly preserved in a state of mummification, was found completely nude.
Introducida no coxín onde repousaba a cabeza da infanta Sancha achouse unha carta, datada o día 22 de decembro de 1868, na que se manifesta: «No ano 1868, reinando dona Isabel II, atopábase o Panteón dos reis nun estado de completo abandono, e o cadáver da raíña dona Sancha, perfectamente conservado en estado de momia, encontrábase en completa nudez.