How to make a conditional statement that checks if the page is the child of a certain page?

global $post;
if($post->post_parent=='certain page'){
/// Her goes your code......
}

Remember ‘certain page’ is your parent page id.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)