He's blunt... I remember the furore over a child being told that he was too fat to be an astronaut. A tremedous public fuss. The child was too young to be an astronaut in any event and, had he really wanted to be, he might have noted that astronauts are quite neccessarily slender. It might have planted a seed in his head that he would do whatever it took to be an astronaut...
My beloved Nana was like this. "Now, little Lying, you don't really want another biscuit, do you? You're getting a little bit big for that dress and it won't look so nice if you keep on eating biscuits". She was very 'to the point' and I loved her dearly even if she would be 'cruel to be kind'.
I think there's a golden middleway between 'shooting from the hip' and the overindulgent, unhelpful reassurance that some people patronise children with.
I miss my Nan... :(