Mine too.
The WHO estimated 570,000 AIDS related deaths in children in 2005.
Giving 570,000 / 365 = 1562 / 24 = 65 deaths per hour.
So the number is accurate; the question is how they define 'child' (prepubescent?, under 10?, 6?) and what they mean by 'AIDS related death'.
Was it secondary infection like pneumonia (probably related to AIDS) or was something like dysentery or cholera (with little-to-no connection to AIDS).
Two questions, actually. What is the definition of "children", as you asked, and what does "AIDS-related" mean, exactly? The "political football" potential for these two items is huge.