when I was in first grade in Washington, D.C. in 1948, our teacher asked us to bring in our favorite book(s) to share. I brought From Egg to Chick, which I had just received as a present. I loved the pictures of the chick developing in the yolk, and finally bursting its way through the shell to the world and its mother. My teacher did not. I was sent home, with my book.
I still love the pictures of the growing bird inside the egg. Sex among birds was not a topic for primary grades. I have not seen the book since then, and am happy it is still around.