Despite all the inevitable changes your kid will certainly go through, they're pretty quick to remind you that, regardless of their age, they'll always be your baby. In the same way your mom probably still thinks of you as her baby, even after you've become a mom yourself, there's really no way to look at your growing little one and not see the tiny newborn you brought into the world. My advice? Just try your best not to tell your kid that when they're 16 and you're dropping them off at school.
The moment I realized my baby was growing up was when he self-weaned. He was half-way through his second year and I found the entire process to be pretty emotional. In many ways I was also ready for the transition, but it was just more proof that my little guy was changing. Shortly afterwards he started pre-school and, once he was bringing home crafts and making new friends, I knew I had a preschooler on my hands, instead of a baby.
I love looking back at my son's baby photos and remembering just how tiny he really was. Still, I am always reminded that he is still my little guy in many ways. He still needs me, my love, my protection and advocacy, and for me to build him up and give him confidence to go out into the big world. So, when you feel like your kid is growing up a little too quickly, just remember that in more ways than one and regardless of their age, they'll always be your baby.