session value can't be store

[davids701124]

I made a form with session method to store particular's id when user is submit new event. however, according to my code, everything was store into the table correctly, except $_session[baby_id], can anyone help out??

 

<?php
//set up session!
session_start();
//connect to db
require( "dbconnect.php" );

//check seesion is set or not
if(isset($_SESSION['username'])){
	echo "Welcome, ".$_SESSION['username'].". ";	
	echo "Your baby_id is ". $_SESSION['baby_id'].".<BR>";
} else {
	echo "please login!";
}

$_SESSION['baby_id'] = $baby_id;

//insert entry
$sql="INSERT INTO post (post_title, post_des, photo1_url, photo2_url, photo3_url, baby_id)
VALUES
('$_POST[title]','$_POST[des]','$_POST[p1]','$_POST[p2]','$_POST[p3]','$baby_id')";

if (!mysql_query($sql)) {
	die('Error: ' . mysql_error());
  	}

echo "the entry is added";
?>

[mikesta707]

where is $baby_id defined

[davids701124]

where is $baby_id defined

 

$baby_id is used to replace $_SESSION[baby_id], it is a id number auto-increasing after user registered.