This can happen in one of the water parks, too. One scary area is the floating lazy rivers, where several children can be hard to keep together with you. We've had close calls there.
We'd always pointed out the red swimsuits and the ID pins of the CMs to all of our children when we entered the water parks. After noticing quite a few red swim trunks on guests, we'd told the kids to identify a woman CM to ask for help if they got lost and to never, ever leave the gate without us.
Our DD was 7 the first time we went to Blizzard Beach and our twin sons were just 5. We all split up for a while as my DH took our DD to the bigger slides and I took our little boys to the Ski Patrol area where the slides are a bit tamer. I asked them to stay together with me and we'd regroup at the bottom of the biggest slide. As a preschooler, David was a fearless child, easily given to wandering or rushing ahead. I'd never lost him before but we'd had our moments. To make matters worse, he is deaf in one ear. If he is turned so that there is noise on his good side while you speak to him from his deaf side, forget it, he doesn't even know you've spoken.
Anyway, he rushed ahead to the slide stairs, all excited. By the time I reached the top, he'd slid down. By the time I slid down, David was gone. Gone completely. Knowing his tendency to wander, I had no idea which way he'd run off or how long it would take him to realize he was lost. I couldn't go to look for him until our other DS had come down the slide and out of the splash pool at the bottom.
In those seconds, the most horrible, panicky, sick feeling swept over me but I had to try and keep calm with Matthew watching. I called out for David, knowing he couldn't hear me with all the music and pool noise. I grabbed Matt's hand and we hurried all around the immediate area looking for him. After a few minutes, I went to a CM lifeguard and told her that I'd just lost my son and he wasn't a strong swimmer. She asked me what he looked like and I just pointed to Matt and said, "like him, but in a red swimsuit!" She radio'd something in and then asked me to go to the First Aid area to make out a report.
Then the tears came. All I could think about was how he'd hated that loaner lifevest we'd made him wear and he might take it off to play in the wave pool or lazy river and now I had to leave the area where he'd last seen me and oh, where was my DH?!?!? When you are thinking these things, the noise of lots of children playing and splashing in the water is LOUD. The CM called for someone to come and take me to First Aid. A pleasant CM arrived quickly and we started to walk off but my mind was racing. Every second was an eternity. At least 10 minutes had passed since David has slid down that slide and out of sight.
We started walking out of the Ski Patrol area and there ahead of us... was David. His face was pale and frightened and he was darting down the path, headed straight for a woman CM in a red suit. I called him but of course he didn't hear me. Matt & I ran to him and we all just huddled crying for a moment.
It took us a few minutes to calm down enough to thank the CM and go back to the slides. After that, Matt & Dave stayed tightly together and I wrestled with fighting back tears for a few more hours. When my DH got back with DD, and I told him what had happened, we all felt so relieved that it had worked out alright. The good thing that came of it was that it was only the second day of our first trip to WDW with the kids. They have always made a big effort to hold hands together with us in any crowds ever since. That was 5 years ago.