The RNLI says the man and boy were were swept out to sea off Aberffraw, on the west coast of Anglesey.
The man was able to make his way back to shore, but the child is still missing.
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Despite ten changes to the side, the Dragons were roundly beaten by Clermont at Rodney Parade.
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A wintry feel tonight, with rain falling as sleet and snow over the hills. We could see ice on the roads, with mist and fog too.