My good friend recently had a baby, and as most people will attest when a momentus event like this occurs, the talk turned to aliens.
One of my coworkers suggested that all babies look like aliens. After spending literally seconds comparing aliens to babies, I've determined that he may be right. For instance, compare this picture of an alien to this picture of a baby. The resemblence is uncanny.
Of course, our perception of aliens may not be entirely accurate. For example, there are a lot of aliens working in Texas, California and New Mexico that just look like hispanic people. And if these people are any indication of what aliens are really like, then at least they have good food. Although baby food is pretty gross, so maybe it's a crapshoot.
Speaking of crapshoot, I bet the aliens in the movies don't need to be changed every hour on the hour. Although they can spit up a lot, as evidenced in The Fly with that Chaos Theory guy from Jurassic Park. And they can come out of a woman's belly, like in Alien 3. So maybe they do have a lot in common.
But who knows? Maybe my friend's baby really is an alien. If so, at least we know that the baby is not an Illegal.