If that were the case and given their reproduction rates the population of both Albania and of "albunny kosovars" should be in the billions. I don't really believe there was such a thing as an albanian prior to the Turkish eruption into Europe in the 1400s.
Albania proper, didn't even exist as a country until 1912, and less than a hundred years later with such high reproductive rates & no jobs to actually contribute to civilization, Albanians began overunning all the surrounding countries.
If anyone thinks that this is just about Albanians hatred for Serbs "because of Milosevic", then look at what Albanians are saying and doing about all the other countries they are trying to overrun and again steal a piece of: Greece, Macedonia, Montenegro and more of Serbia.
The fact that you don't believe it means nothing. Read Dusan's code http://www.serbianunity.net/culture/history/Serb_History/Rulers/Dusan_code.html and let us know what you believe again. Serbs are russian nomads and Albanians are autochtone, taking back their land (once again!)
Being as smart as you are you should know that Serbs had the same birth rates until a few decades ago.