Now their are those even I that think Charlie's real mother is Eve due to the little sound lives were made in his fight with Adam just to spite him but there's only one way to test it.

The solution to test it is simple if Alistair got Charlie on his leash on the third deal you may say as a bargaining chip but that contract could be in blood ink but love may have her name on the Contracting question but not her blood, what could happen if that be true well simplest thing that I could think could happen is that Charlie be banished to Earth and here's where my part of Theory comes in let's say the Eve that she's a donor to could be a namesake to the actual person now there's a punchline.

One final note if a third season will have an earth in its First Act will there be those and if necessary Lilith we'll see Charlie as a loose end and we'll send those to keep an eye on her and if she tries to get back may have to end her and that may know who they will send first before going to plan B.