Likely the chronological age, mainly because it would explain the differences in puberty stages between the two boys, which is an example of physical maturation.
1) refer them to a hotline, it’s always best to ask for help from a trusted and reliable adult.
2) acknowledge their pain and be there for them; don’t ask them questions such as “what were you wearing?” or “why were you even there?”, it is NEVER a victim’s fault, make sure they know it’s always the perpetrator’s wrong.
3) make sure they are safe from there, ask if you can accompany them so you make sure it doesn’t happen again.
