Tinok Yonek Mshdei Imo

The gemorah mentions that the third mishmar is identifiable by a child nursing from his mother and a women talking to her husband. What simun is a child nursing? A child nurses a few times each night? Also, their is not much noise involved with a child nursing? How can that be a simun?
The Ben Yehoyadah answers that the true simun is a women talking with her husband. The child nursing is an indication that time has arrived. How so? Although a woman does nurse a few times a night normally she does so lying down on the bed half asleep. By the last feeding of the night though, the woman is well rested and usually sitting up and feeding her baby. She is wide awake and is then talking with her husband who is now presumably awake as well. You can also be mediyak from the lashon. It says that the baby is nursing "mshdai imo". That implies that it is a more formal nursing as opposed to the mother just lying down and the baby eating. I thought that was an intersting Pshat.