"Sexual abuse" means any contact, however slight, between the sex organ or anus of the victim or the accused and an object or body part, including, but not limited to, the sex organ, mouth, or anus of the victim or the accused, or any intrusion, however slight, of any part of the body of the victim or the accused or of any animal or object into the sex organ or anus of the victim or the accused, including, but not limited to, cunnilingus, fellatio, or anal penetration. Evidence of emission of semen is not required to prove sexual abuse.
720 ILCS 5/11-9.1B