Caedea, a huntress and the mother of Proca by Janus, is the goddess of thresholds and especially door-pivots (cardo "door-pivot"), health (akin to Carna), and family in Roman folklore.
Cardea is the protectress of little children against the attacks of vampire-witches.
It is said that she used to be seen as a two-faced goddess perhaps indicating a dual nature...
She obtained the office from Janus in exchange for her personal favors. She lured Janus into a cave and tried to run away but he saw her with his other face and caught her.
She was given the power to repel demons and bore a son, Proca. However, this story is also told of the nymph Carna.
Some identify Cardea with Eurynome, others with Artemis, Carna, Carnea or Rhea...
Reources:
See Rhea:
Image adapted from: http://bit.ly/1hdVxlS