My Stepson Makes Me Nervous

My stepson (16) makes me so fucking nervous. I've been in his life since he was 10. Their mother is MIA. I'm really comfortable around his younger brother who's 14. His younger brother and I are really close. I have always wondered why he makes me jittery. While driving I could feel him staring at me. We barely talk and I believe because everytime I hear him it feels like my brain gets scrambled and I feel like a deer in headlights.

There's been times that we hugged and he wouldn't let me go. He would hug me for 5+ minutes. I chucked that up to his mother not being in his life. But then I notice the way he stares at me makes me shrink. He gives me the most intense eyes and it reminds me of how his father would look at me (he looks exactly like his dad.)

Idk I just needed to get this off my chest.