I'm a Leo, but definitely not a typical one- for example, I'm an INFP, was very shy when I was younger, much more inward-focused, and am affected a lot by what others say or think. I think I have more water sign tendancies and never really identified much with being a Leo or liked them. Anyhow, my DS is also a Leo and though he is more outgoing in public than I was as a little one (but balanced, not running away all the time or clinging to me), he is still very giving for a 2 year old, gentle, and concerned with how others feel (pats owies, etc). I don't know if this has anything to do with his sign, but he is also very speech delayed with expressive communication but understands and follows instructions well. But, this doesn't stop his love for people as he gives a big smile and wave whenever he seems someone (even strangers).
I'm not too concerned with this baby also being a Leo, as none of the Leos in my house seem to have what I think of as the 'bad side' of being a Leo (overly self-centered, stubborn, rash, etc). Like PP stated, there are so many other variable that come into account when interpreting your sign- you may not exhibit all or even most of the traits of the sun sign.