I agree with that. I really like toddlers in The Sims 4. I couldn't even imagine the game without them, even though it was before the update for Vampires game pack came out and I was also playing the game back then (I still have footage to a baby growing into a child straight away). It was worth the wait.
Plus I like how they develop in that life stage. At first, they use their diapers, babble, walk clumsily etc, but as they play and learn, they use their potty, actually talk simlish, run around etc. Plus they have even more interactions with children than before. And instead of just hugging pets, they can now pet them and imidate them. Plus they can now use stairs.