<?php
$tests = [
"Apelido\n\nFulano de Tal",
"Apelido:\nFulano de Tal",
"Apelido: Fulano de Tal"
];
foreach($tests as $test) {
if (preg_match("/(Apelido\:?)(\s+)(.*)/", $test, $matches)) {
echo $matches[3], PHP_EOL;
}
}
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