so even then, even if every family was 2 adults and 2.4 children your are still only talking about maybe 300 aliens. im tempted to watch aliens again and make a rough estimate of how many were killed in that
60....maybe 70 families.
In terms of alien numbers how many colonists were there anyway? The aliens weren't limited in number in the movie. I guess though many were in the nest in the reactor so many would have perished in the explosion so numbers will dwindle by the time Colonial Marines picks up the story.