Did I exist?

Tanya Reimer brought up a good point in her comment on my post. If you don't remember it, does that mean it didn't happen? So, I'm in a dilemma here. You see, I don't remember anything from age 3 or 4. Does this mean nothing happened? Does it mean I didn't exist at that time? I think something did happen at age 3 and 4, because my parents tell me so. (Does that give me legitimacy?) They tell me they bought me a dog. They called him Jip, because they paid so much for him. And I ran over him with my tricycle (he lived, no serious injury). I do not remember this. It did not happen.