Sorry shielsey my son s only 8 so his shirts wouldnt help with size advice !
however, my daughter has a few things from more mile in boys sizes and she wears medium boys (shes 10) and she has a friend whos 11 at wears large boys more mile but i still wouldnt have thougght they were much above a size 6-8.
Xl - yes im looking forwrd to the cookson, off to do the greggs run with the kids tomorrow and planning on running to the racecourse from mine to squeeze in my long run.
Fiona - yes i am laying the decking in is rain ! Out all day tomorrow so it needs to be finished today, having a 5 min coffee break now and then back to work