A kid in my geometry class came by and told my brother with social anxiety "fuck you".

For this rant, I'll call him "Ricky". I have had problems with Ricky for a while from my past experiences with him, but today he crossed the line when messed with my brother. My brother is older than me but is Autistic and has social anxiety. I was able to get him to come with me and our little brother to the park. And who would be there, Ricky. My brother was just hanging out, minding his business watching my little brother do his baseball practice with me. When Ricky drove by on his bike, and yelled, "Fuck you" to my brother. My question to the people of Reddit, how do I handle this situation?