I have memories from as young as two years old. My primary stream of memory begins at age three when my family moved across the country...a very easy marker for me to go by.
I actually wrote down all my earliest memeories many years ago...and then I was able to confirm the timeframe talking to my parents. My earliest memory was in the nursery at my parents' church when I was right about two years old.
By the way, I don't believe Mikey remembers his birth either. My guess is that he's remembering a dream. Some of my earliest memories are dreams.
Memory is a weird thing (so maybe never say never to Mikey's claim)...because it has been demonstrated that infants who cannot speak yet do have memories of past events. But, yeah, somewhere along the line we lose those memories. There appears to be a relationship with the development of language skills.
I have a toddler myself and I have tested his memory. After a trip to Chicago shortly after his third birthday, I could show him pictures of the people we visited there and he could name them and recall things we did. Nine months later, I show him the pictures and ask him if he remembers them and some he says no, others he says yes. He can't remember any of their names anymore. He does remember flying on the airplane.
Likewise, virtually all of my early memories were "memorable" experiences; few of them are mundane...mom digging a slug out of the garden, my brother's new bicycle, a giant gravestone, a hotel swimming pool, tasting dog poop...and, yeah, it tasted like poop.