I am getting following error on line 42 of my code. But strange thing is I am already checking for null and the actual error seems to be happening on line 44. How to fix this issue?
Error
Uncaught ErrorException: htmlspecialchars(): Passing null to parameter
#1 ($string) of type string is deprecated in /var/www/mysite/mypage.php:42
Code
while($row3 = mysqli_fetch_assoc($result3))
{
$emailbody .= "<b>Keyword:</b> ". htmlspecialchars($row2["keyword"]) ."<br>";
if(!is_null($row3["summary"])) //line 42
{
$emailbody .= "<b>Summary:</b> ". htmlspecialchars($row3["summary"]) ."<br>";
}
}