It might sprout- but not in your stomach, but in the ground somewhere after it passes through your gut!
That's how seeds are spread by birds who eat their berries, and that's what just might happen to a watermelon seed you eat!
(No, it won't sprout in your stomach! If it did it couldn't grow- there's no sunlight down there!)
(That's the same reason you know there are not alligators in the sewers in New Jersey- there's no sun down there for them to sun themselves in!)
God loves you! Birds do it all the time!
Sincerely,
David S. Annderson