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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Two men were taken to hospital after being rescued off the coast of Aberystwyth this morning. One is said to be in a critical condition.
A mixed forecast over the next few days, including outbreaks of rain.
MPs should be given an allowance instead of having to claim for expenses, the shadow Welsh secretary has suggested.