My son was two and I was pregnant with my second child. We had ended up co-sleeping with our son (family bed), and expected to (and did) co-sleep with our second and third child as thy came into the world. While I was pregnant with my second child, I sold the crib that had only been used for portions of two nights to a very confused looking pregnant woman. I wanted it out of storage. My son had never seen used, except to store unfolded laundry and cloth diapers.
We went to a friend’s home for a play date. She had a little boy who was the same age as my son. She also had an infant daughter. When we arrived, my son wanted to see the new baby and my friend told him that she was just waking up from a nap and that he could follow her to see the baby.