DS2 has always been incredibly skinny, it was picked up by the school nurse too who said he was actually underweight. He's 10 now and weighs just under 4 stone. He can still fit into age 5-6 boxer shorts. He doesn't eat much, leaves most of his dinner most nights and generally has a poor diet (although I do try!).
Anyway recently he's started eating A LOT. For instance, this morning he ate two bowls of cereal PLUS peanut butter on toast and then he was asking for other stuff. He very rarely brings any pack-up home now and he's even started eating his dinners properly. Another change in him however is a very odd sleep pattern where he wakes up at 3-4am, wonders around the house, watches TV (without me knowing as I'm in bed obviously) and eventually drops off back to sleep around 6am - and then struggles to get up at 7am and is AWFUL all day (behaviour and attitude). Could the eating and change in sleep be connected??