Very advanced.

My beautiful nephews are two years old and three months old. I was in the other room when baby Miles wailed sharply and then Isaac started to cry. I came in to find my sister comforting Miles and Isaac coming to me to be held. I scooped him up and asked him what happened. He choked back sobs and said "Miles got hurt." My mom skills are not fully developed, so I was still wondering why Isaac was crying when my sister said "Nice use of the passive voice there, bud."

At only two! Using the passive voice properly! To denote an agentless accident that somehow ended in his baby brother crying! To obscure the subject, who might otherwise be confused for a little boy in the very same room! Nicely done, sweet Isaac. Your grandfather will be so proud.