Sam Simon, the nine-time Emmy winner who helped to create "The Simpsons," passed away Sunday of of colorectal cancer. He was 59.

A television comedy veteran whose credits included "Taxi," "Cheers," "It's Garry Shandling's Show" and "The Tracy Ullman Show," Simon developed "The Simpsons" in Matt Groening and James L. Brooks, and co-wrote almost a dozen episodes. During his time on the series, Simon served in several roles, including co-showrunner, character designer, creative supervisor and creative consultant.

"He was a genius and a great humanitarian in ways public and private," Al Jean, executive producer of "The Simpsons, said in a statement. "I personally owe him more than can be repaid, but I will do my best to help every animal I can in his memory." He added on Twitter, "If you would like to honor Sam's memory, do something nice for the next animal you meet. An enormous loss."

Simon left "The Simpsons" in 1993 (he retained the title of executive producer, however), and co-created "The George Carlin Show," but spent much of the decade working as a director.

A staunch advocate for animal rights, he sought a life "outside of television," and in 2002 established the Sam Simon Foundation, which rescues and retrains dogs that would have otherwise been euthanized. However, his philanthropy reached well beyond that, to Save the Children, PETA, the Sea Shepherd Conservation Society and other organizations.

Following his diagnosis with terminal cancer in 2012, Simon began buying roadside circuses and zoos and freeing the animals to live out their lives in sanctuaries. He also paid $60,000 to rescue an abused thoroughbred horse, and helped to ensure a bull that was more interested in other bulls than cows wouldn't be sent to the slaughterhouse.

"When I was sick, I got to summon people to my hospital room. Ingrid and I got this fun idea. I started to buy these zoos and circuses in December," he told The Hollywood Reporter in 2013. "I just wanted to have some days where I get to see animals walk in grass for the first time. Through PETA, we rescue animals in roadside zoos and circuses. They are some of the most abused animals in the country. Freeing those animals, that's something I'm not sure I would do if it weren't for the cancer."

In a statement, the Sam Simon Foundation said, "We all miss him, and in his honor, we will continue bringing his vision to light through our work at The Sam Simon Foundation. We take comfort in knowing how many greetings he is receiving across that Rainbow Bridge."