This might sound like a stupid question..but first, two basic definitions for gravity:

The natural force of attraction exerted by a celestial body, such as Earth, upon objects at or near its surface, tending to draw them toward the center of the body.

The natural force of attraction between any two massive bodies, which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.


My question is: How is it that there is a planet, when in fact the gravity needed to draw that which would make up the planet to the planet wouldn't exist until after the planet reached a substantial amount of size?

Pretty much: How the hell did gravity even get going in the first place?