Is it normal friend made me touch kid?

I'm really embarrassed and ashamed about this, I was 10 years old and I was friends with a boy who lived in my street who was around 15 or 16. We use to babysit this kid who was around 5 years old when his parents went out for an hour or two. I only did it because we were promised like $20 each time we did it.

Though my friend hated the kid, I never knew why and when his parents left my friend would abuse him (kicking him, tripping him over, punishing him for no reason, not giving him dinner etc.) I always felt bad but I was too scared to tell someone about it.

One day when the parents left my friend made me touch the kids private part, I didn't want to do it and kept saying no but he kept saying I had to do it. I only touched it for a few seconds, I didn't feel him up or anything (which is still really gross though) and I felt so bad about it after. Worse thing is there were times where my friend would be left alone with the kid without me, he could of been doing many other bad things that I didn't know of.

I was a stupid kid back then and did whatever my friend told me, he never physically hurt me and was actually very nice to me, but he was a good liar and usually tricked me into doing things for him. The times I refused he'd get kind of scary, not overly showing it but it was like he was being nice but underneath actually threatening me.

This was mostly when things escalated, but shortly after the incident my family was forced to move house because we got kicked out. I'm kind of glad that happened because I never saw him again.

I've never told anyone about this, I know I didn't actually DO anything to the kid but whenever thinking about it it's really gross and i think i deserve to go to jail for it because it's so wrong.

There is no use in doing anything about it or going to the police because this was really long ago, I'm an adult now but I still feel so guilty about it