I think you send them in if you possibly can - dosed up on painkillers, etc if necessary. And if they are really too ill then you contact the school first thing, and also get a GP appointment for that day to certify that they're ill.
Am also hoping not to have to put this to the test. Thankfully threatining a scribe and GP review of the "injured" hand seemed to be sufficient to bring about a recovery for DSD and her only complaints so far have been that biology was obviously horrible because it was biology so what did we expect? No mention of injured hand limiting her thankfully.
Hope your DS2 gets better soon, green - yes keep him shut in his room and take food to him - and if you have two toilets/bathrooms, let him have one of them all to himself for a few days.
DS has an after school session today to go through his disasterous geography paper, and hopefully learn some exam technique. Anyone know the rules on when they need to answer in complete sentences and when bullet points will suffice?