As shown in the quotes below:

"....The Tannaïtic Midrash Sifre to Numbers in §157 comments on the above quoted commandment of MOSES to kill the Midianite women as well as the male children...."



"....According to the Tannaïte Rabbis, MOSES therefore had ordered the Israelites to kill all women older than three years and a day, because they were "suitable for having sexual relations." [138]...."



"Said Rabbi Joseph, "Come and take note: A girl three years and one day old is betrothed by intercourse....."



"A girl three years and one day old is betrothed by intercourse. "A girl three years old may be betrothed through an act of sexual intercourse," the words of R. Meir. And sages say, "Three years and one day old