Rap mogul Russell Simmons and his wife KIMORA LEE's troubled marriage has gone to the dogs - they're both committed to raising awareness about the dangers of chaining pets up outside. The couple, who recently split after seven years of marriage, are donating time and cash to help People for the Ethical Treatment of Animals (PETA) activists highlight the plight of pets left out in the cold. Model-turned-designer Kimora has donated $20,000 (GBP11,100) to the cause, while Def Jam Records co-founder Russell has shot a public service ad to warn people about the dangers of leaving their dogs tied up alone. He says, "You should take your dogs inside... Your dog's not going to be smarter or tougher or more resilient because you make him suffer."