These days the kids are really fast in achieving every milestone. And the same holds for development of parent recognition. Kids as small as 5 months like to stay with their mothers only. I was shocked to see the behavior of my sister in law's 5 month old son. She had gone for some errands and had left him behind. For the whole one hour he kept yelling at the top of his voice. As soon as she came back he stopped crying as if nothing had happened. He developed parent recognition and stranger anxiety pretty early. Isn't it?