An 18-year-old man from Luton has died in hospital after he got into difficulty in the sea near Clacton Pier on Thursday, Essex Police said.
Haider Shamas died in hospital on Saturday, two days after the incident in Clacton that also claimed the life of his 14-year-old sister Malika.
A 15-year-old girl, a relative, who was also got into difficulty while swimming, is expected to make a full recovery.
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