This video made me write about an incident we had in Westfield Stratford just recently:
I used a harness on my son when he first started walking but couldn't use since he turned 2, as he completely refused to put it on. He is 3.5 now and doesn't want to sit on his buggy either.
Recently I was at H&M with him and kept him next to me at all times. On the way to the till he just disappeared. I kept calling him very loudly and run around to find him. Staff of the store also started looking for him everywhere and finally one of them found him at the other end of the children's department.
He said that he was going to play hide and seek with me but lost me out of his sight. I don't know why he didn't answer me when I called him so many times. It took about 4 minutes to find him but it was one of the scariest moments in my life.
Indeed, it takes just a split second to lose your child. Be careful and watch out!