I doubt it. It’s a direct reference to the book. To be a sweet summer child in the book is to be naive about the winter that is eventually coming, since you’re too young to have ever lived through a winter before, and therefore have no idea or conception or experience of what the real world is actually like. For those who don’t know, summers and winters are exceptionally long in the fantasy world of Westeros, and if you were born at the beginning of summer, you could reach the age of 10 before ever knowing a winter.