Board Thread:Spoilers!/@comment-25613119-20150304154923/@comment-24936039-20150312024000

Here's a summary of my speculations (which I have posted dribs and drabs here and there on other threads)

Lily's father - Hong Kong Dragon (and Maleficent's true love I don't think Villains are disqualified from having love interests) - people have been wondering since season 1 how he came to the LWM - I suspect by the same means that Curella and Ursula did.

Charming's dark secret - causing (when there were alternatives) Maleficent to lose her baby (and mate?) and from escaping the first dark curse. As someone mentioned, the QofD may of devised their own escape plan or at least not to be fully trapped in Regina's Storybrooke without memories (or worse). The Charmings likely did not know what became of baby Lily and presume she is dead (hence their great angst and extreme horror of being found out, especially by Emma.  They after all are heroes.... right....?)

Cruella is Lily's adoptive mother - Ursula and Cruella ended up in LWM (with memories intact) but outside of Storybrooke with baby Lily. They parted ways, with Cruella ending up as the adoptive (likely abusive) mother of Lily. I get the impression that in the LWM, that Ursula and Cruella were not much into keeping in touch with each other through the years.