Yes some do. Even some adults were mean to me when I was a child. I played in a kids league soccer team and I remember some of the other kids parents making jokes about me on the sidelines. One example of adults being cruel that really stands out to me, was when I worked a fast food job as a teenager. One day I was handing back a lady’s change and I stuttered. She put on a cruel smile, put her hand over her heart, looked at her husband and giggled. Then she asked me in the most condescending ‘sweet’ voice “are you stupid?” I said “no I just stutter” and she laughed again before she walked out. Now that I’m an adult and my stuttering is less severe, this doesn’t really happen to me anymore. But yes adults can be as cruel as children, and it’s actually worse because they especially should know better.