Shortly after the U.S. Coast Guard announced Monday night that it was ending the 3-day search for his son Tristen, Sam Allen took to his Facebook page to thank everyone for their help and prayers and explain that the second phase of the search would soon begin.

"We can't say thank you enough," the elder Allen wrote. Tha island has is alive with the spirit of Tristen and we can feel his love all around us."

Friends of the 18-year-old James Island Charter High grad also took to social media to share their thoughts, prayers and memories.

A #prayforTristen hashtag was started on Twitter. You can follow it here.

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