Using variables with mail()

[Anon]

Hello, I have a script set up like this (simplified):

$vondu = "turtle";
$message = 'This is the message\n
Today we will be serving $vondu\n
Please come.
';

I want to have a mail() command like this in the script:
mail("[e-mail]","your message",$message);

But, when I do that, the message appears as:
This is the message\n
Today we will be serving $vondu\n
Please come.
instead of:
This is the message
Today we will be serving turtle
Please come.

How can I get this to work the way I want it to?

[Anon]

Also I should add that $message and $vondu are defined in a different file than where the mail() command is. include is used to put them in the file with mail().

[Anon]

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