This appears to be a work of fiction.
Stories like these are retold a million times at home. And even if you were too young to remember the actual incident. The repeating of the story would leave you with a memory clear as crystal.
The heart of a parent skips a beat if they lose sight of their young child for even a moment. Half an hour is a lifetime.
In today's day and age of over protective parents a scenario like this would be an absolute nightmare.