If one is stealthy enough and works hard enough in the right areas, one might even get very lucky and see an adult with its fluffy black offspring (almost all baby rails are fluffy and black - check it).
Of course if you don't want to work that hard you can always pull up a stool and a beer in an island bar and wait for one to walk in and try to steal some spilt bombay mix.
White-breasted waterhen in natural habitat!
I walked around Biyhardoo for a while trying to take some shots of these and a couple of other things and generally failing, so I gave up and went for a beer when this happened. The truth is the bird with the chick is the same bird in the above shot. It ran out of the bar to the chick whereupon they both disappeared into a small woody copse which is where the very top photo was taken.