Does touching the private parts of a six-year-old child invalidate ablution?

Scholars have differed on the nullification of ablution by touching the private parts of a child, holding two opinions: The first is that touching them nullifies ablution, just as it does for an adult. This is the view of Ibn Qudamah and the Permanent Committee for Issuing Fatwas. The second is that touching them does not nullify ablution. This is the view of Az-Zuhri, Al-Awza'i, and Ibn 'Uthaymeen, who holds that touching the private parts does not nullify ablution unless it is done with desire, whether for an adult or a child. The more probable opinion is the second one, because it is a widespread occurrence, and there is no evidence that touching a child's private parts nullifies ablution.