I found out last night that ds was involved in an incident where a group of older children lifted him up and repeatedly pulled his pants down. I didn't collect him from school the day it happened or yesterday and both nights he was asleep when I got home but his grandparents (who due to me being away during a school trip have been given permission to deal with anything) were not told.
The first I knew about it was a text from a friend apologising as her child was involved on the periphery and they have had a letter home. Ds told his grandparents last night he was very upset about it at the time.