Hi, my lb is 3 next month a a and has for the past two months been toilet trained doing great 
We haven't been to a soft play since starting tt but went today.
I saw my lb with another boy much older, about 6/7 stood upstairs. My lb dropped his trousers and pants so I immediately legged it up as I thought he was about to have a wee
However, when I got to him I said what are yoh doing do you need a wee to which e replied "no I'm just showing this boy my willy" I was so shocked. I asked the little boy who was looking rather sheepishly why and my lb said he asked to see it. I then asked the boy why he asked to look at his willy and asked for hkm to show me his mommy. He ran off and went down the slide. I followed and told his mum what had happened. She got funny with me at first but then told him off in a fashion.
I'm just shocked and saddened at how this demonstrates the naivety of our young and innocent children