Whatever the case, it is certain that Janus and Juno show a peculiar reciprocal affinity: while Janus is "Iunonius", Juno is "Ianualis", as she presides over childbirth and the menstrual cycle, and opens doors. Moreover, besides the kalends Janus and Juno are also associated at the rite of the Tigillum Sororium of 1 October, in which they bear the epithets "Ianus Curiatius" and "Iuno Sororia". These epithets, which swap the functional qualities of the gods, are the most remarkable apparent proof of their proximity. The rite is discussed in detail in the section below.