The two celebrities have joined Shaquille O'Neal and the stars of The Buried Life by vowing to keep silent for 24 hours on November 30 to support of children living in poverty, hunger and disease across the world.
The Vow of Silence campaign is sponsored by Free the Children, an organisation dedicated to empowering youth.
"For Vow participants, being silent can mean refraining from speaking," reads the website. "It can also mean not using email, Facebook, Twitter or text messaging. It can even mean not using hand gestures, note writing or any communication at all.
"Participants like you can determine your level of silence based on what you're comfortable with," the statement concludes.
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