Sun Pregnant - Who Really Killed Shannon?

Okay... so just finished reading Kristen's chat transcript... and it said that Sun is pregnant (duh) and... (this is the good part)... the Others couldn't be happier? This would make sense, considering the obsession with all the children on the island, but here's my question:

If Shannon were still alive, her and Sayid would be having a lot of "private" time in the love shack, and there is a very limited amount of profilactics on the island (although who knows what's in the hatch)... eventually, there is a good chance that Shannon would get pregnant.

Think of all the kids we know who have already gotten taken: Walt (both his parents were Black), Alex (we assume both her parents were White/French), Aaron (both his parents were White/Australian)... and if Jin and Sun were to have a baby that was going to make the Others "happy", that means they might try and take the new baby, whose parents would both be Korean.

Now, back to the original thought of Shannon getting pregnant... if she were to have a baby, the baby would be half White/American and half Iraqi... this does not fit with the theme of the children that were taken... there has already been a lot of speculation as to whether Ana Lucia really killed Shannon (and although I know the majority decision was that she did in fact shoot her, there is still some doubt about hearing a second gunshot.) But what if the Others shot Shannon framing Ana Lucia, or at least created the condition that would make Ana Lucia shoot either Sayid or Shannon (they started the whispering) so that they could not have a "hybrid" baby? I have no clue where to go from here, but I think I could be on to something!!