The two stars will join Martina McBride in support of music charity Musicians on Call, which honoured Clarkson last year (14), at the Rock the Room show next month (Oct15).

The three women will be joined by other special guests at the gig, which will benefit an organisation that helps to provide live and recorded music to hospital patients across America.

MCBride tells RollingStone.com, "Musicians on Call is truly an inspiring and wonderful organisation..."

MCEntire adds, "I've been very fortunate throughout my career to witness first-hand the healing power of music. I am so honoured to support Musicians on Call."

Rock the Room shows will also take place in New York, Los Angeles and Washington, D.C.

MCEntire broke the news of her separation from husband Narvel Blackstock last month (Aug15) after 26 years. Blackstock is the father of Clarkson's husband, Brandon Blackstock.