DD (age 11) is growing unbelievably fast (6 cm and a shoe size since September). She was previously very healthy, but now catches everything - tonsillitis, flu, and so on. It seems like every other week she's poorly and it takes a while for her to recover. She has a good diet and exercises (when not ill), and usually gets enough sleep - in fact she seems to need quite a lot at the moment, around 11 hours a night. She's getting fed up being poorly and missing activities, but I don't know how to help her stay well. Has anyone else experienced this? I wonder if growing is just taking up all her energy.