tlacatetehuitl.

In Primeros Memoriales it is explained that after several years of drought, when people were starving, people would take their little children and sacrifice them. This, it was believed, would restore the rain and, therefore, food. (sixteenth century, central Mexico)
Fray Bernardino de Sahagún, Primeros Memoriales, ed. Thelma D. Sullivan, et al. (Norman: University of Oklahoma Press, 1997), 249.

Yoan vmpa qujmoncaoaia pipiltzitzinti, in moteneoaia tlacateteuhti: iehoãtin in vntecuezcomeque, in qualli intonal: noujan temoloia, patiiotiloia = And there they took children, known as "human banners"--those who had two cowlicks of hair and whose day signs were favorable. They were sought everywhere, and brought. (sixteenth century, central Mexico)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2 -- The Ceremonies, No. 14, Part III, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1951), 42.auh muchinti, ynmaxtlatzon ietiuh, quetzalxixilquj, quetzalmjiaoaio: in chalchiuhcozquj ietiuh, yoan momacuextitiuj, qujmomacuextitiuj chalchiujtl: tlaixolujlti, qujmixolhujaia, mjxmichioaujque, yoan ymolcac, ymolcac ietiuh, muchintin maujzçotiuj, tlacencaoalti, tlachichioalti, muchi tlaçotlanquj, yn jntech ietiuh, tlaçotlantiuj, qujmamatlapaltia, amatl, amaamatlapaleque: tlapechtica in vicoia, quetzalcallotiuja yn vncã momantiujia, qujntlapichilitiuja = And all went with head-bands with sprays and sprigs of quetzal feathers; they had green stone necklaces, and they went provided with green stone. Their faces were painted with liquid rubber, and spotted with a paste of amaranth seeds. And their liquid rubber sandals: they had sandals of liquid rubber. All went in glorious array; they were adorned and ornamented; all had valuable things on them. They gave them paper wings; wings of paper they had. They were carried in litters covered with quetzal feathers, and in these [the children] were kings. And they went sounding flutes for them. (16th century, Mexico City)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2—The Ceremonies, No. 14, Part III, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1951), 43.

auh in pipilzitzinti, intla chocatiuj, intla imixaio totocatiuh, intla imixaio pipilcatiuh, mitoaia, moteneoaia, ca quijiauiz: yn imixaio qujnezçaiotiaia, in qujiaujtl = And if the children went crying, their tears coursing down and bathing their faces, it was said and understood that indeed it would rain. [For] their tears signified rain. (16th century, Mexico City)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2—The Ceremonies, No. 14, Part III, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1951), 44.

tlateteuhtique = fuergon convertidos en tlacateteuitl [o sea, posiblemente "fueron sacrificados" o "fueron empapelados con banderolas de papel ennegrecido"; o tal vez se convertieron en sacrificados a los tlaloque, deidades de la lluvia (Quauhtinchan, s. XVI)
Historia Tolteca-Chichimeca, eds. Paul Kirchhoff, Lina Odena Güemes, y Luis Reyes García (México: CISINAH, INAH-SEP, 1976), 138 y ver nota 11.

tlacatetehuitl = "los niños...que iban a ser sacrificados a los montes (o en Pantitlan), eran vestidos con papel de color y diseño según el monte que les tocaba (Sahagún, 1989, lib. II: 105), y esto parece estar reflejado en las imágenes de los códices Tudela y Magliabechiano". (p. 101)
Katarzyna Mikulska, "Te hago bandera... Signos de banderas y sus significados en la expresión gráfica nahua", en Los códices mesoamericanos: registros de religión, política y sociedad, Miguel Ángel Ruz Barrio y Juan José Batalla Rosado, coordinadores (Zinacantepec: El Colegio Mexiquense, 2016), 85–133.