The X Factor duo celebrated "21 years being twins... brothers... and best friends" today (October 16) and were contacted on Twitter by their Hollywood buddy.
"I want to wish my bff's John and Edward grimes happy 21st birthday," Reid wrote. "I wish you both all the love, luck, and health in the world! I love you!"
The American Reunion star then sent them another message direct to their Twitter profile reading: "May all your dreams come true! I love you and this is gonna be your best year! X."
Reid later revealed that she had recorded a birthday song for Jedward on their voicemail.
On their own Twitter feed, Jedward declared that they "were born to make a world full of Positive Energy and Make People Happy".
They also treated fans to a live video stream in which they showed off their presents and scoffed birthday treats, including a birthday cake with '21' iced on top.
Jedward and Reid became friends after entering Channel 5's debut series of Celebrity Big Brother in August 2011.
The actress later appeared in the Baywatch-themed video for their single 'Wow Oh Wow'.