The former Girls Aloud star and 'The Voice' coach are in mourning after music manager Nick Lauher died.
Nick was part of the management team who helped guide the Black Eyed Peas to international stardom and became close with Cheryl through her friendship with will.
will.i.am is said to be 'utterly devasted' by the news, while his bandmate, Fergie, is also said to be in shock.
A source told The Sun: “Will.i.am has been left utterly devastated.
“He worked with Nick for a long time and had become close friends over the years.
“Cheryl grew to know Nick well due to her friendship with Will.
“She has cleared her diary to go to San Diego. She wants to be there to support Will.”
The news comes the day after Cheryl gave her biggest hint yet that she will return to 'The X Factor' after she took to Instagram to post an old snap of her on the panel with Simon Cowell.