I think it's ridiculous that primary school children are put under pressure to have 100% attendance.This child had a good reason to be absent,as do most children who are off school.Yes school's important but if you've a good reason your child should not be penalised.
Our older children's primary school has certificates and awards for attendance,the first thing you see when you walk into the school is an attendance chart,class by class.That's how important it is,one of the rerasons my younger children go to a different school.
Children get bugs,they get ill,they miss school.If your child is ill they should be at home.Instead far too often they sit in class feeling rotten,sharing their illness with their class mates,who bring it home to their families.Children get ill,it's part of growing up.Being at school,however your health is not some great achievement.Certainly not warranting some special reward.