Can a 7 year old girl molest an 8 year old boy?

Can a 7 year old be responsible for either instigating or participating in sexual contact as a result of having been exposed by an older person? Where is the line between molesting another kid and engaging in sex play together?

The cousin who stole my car just told me he feels like I molested him b/c when I was 6 or 7, I used to "force" him to give me oral sex, and that I need to take responsibility for hurting him.

He said that he forgave me, so why can't I forgive his (7 years older) brother for hurting me?

I don't remember forcing his violent 8 year old self to do anything, nor do I feel that sexual interactions between mostly same age kids vs a 7 year old and a 14 year old are the same thing.

Opinions? And don't hold back for fear of hurting my feelings.