There is a simple way to retouch fireflies in renders with just a few clicks.
This is not a substitute for a nicer render but good enough (especially for previews).

1. Open the image in Photoshop
2. Convert it to 16 or 8 bits per channel. The filter doesn’t work under 32 bits/Channel.
   I suggest that you use the Exposure and Gamma method (Image->Mode menu).
3. Filter->Noise->Dust & Scratches…
   Radius: 1
   Threshold: something low (0-10)

Unfortunately the image will loose some detail (not that much, e.g. you can see it at the mother’s left hand).

Cheers, D

The full res images: