Mythological Headache

I have recently come upon a contradiction in mythology. You might say, 'that's 'cause it's mythology, not history', but this is more serious than whether a crab was involved in a certain labor of Hercules or not. Namely, when was Eros/Cupid/Amor born?? and to whom??? One source (D'Aulaire's Book of Greek Myths) says he was the son of Aphrodite/Venus/Lady of Cythera, and another (Guerber's Myths of Greece and Rome) that he was born to Aether (light) and Hemera (day) before the beginning of the world.
Imagine how frustrating!!!! If anyone has any explanation for this calamity I would be most grateful for it. Is there a preferred version??? Are there two different gods of love, as there are two sun gods???