Swim-Ear is a product to help dry water trapped in ears after swimming, diving etc. It helps to prevent ear infections through removing excess water so bacteria can't breed effectively. It isn't intended to be used as a treatment or anything, just a preventative measure.
There are restriction on its use if you've got ear infections, perforated ear drum etc and you should consult your doctor in which case. This is what the product label says (hope you can read it!):

Its fine for children to use.
Darren