Animal lovers across the U.S. are grieving the death of Sam Simon who spent much of his time and money helping needy animals. 

Simon, who was also a co-creator of "The Simpsons," died Monday night following a battle with colon cancer at 59-years-old. 

His death was announced via his charity's, The Sam Simon Foundation, Facebook page

The foundation, which offers free surgeries for cats and dogs, was created and 100 percent funded by Simon in Los Angeles. He refused to accept public donations and never charged customers seeking services from them. 

As if that weren't generous enough, Simon donated the bulk of his $100 million fortune to The Sam Simon Foundation, reported The Wrap. The rest of the money was donated to other charitable causes. (Simon was divorced when he died and he has no children.)

The PETA Foundation, where Simon was the Honorary Director, dedicated a lengthy tribute to him Monday citing his long list of contributions to the well being of animals. 

"The world could learn all about kindness from Sam's example, just the things he said, and I hope everyone who hears about him will do something kind and generous in his honor, even give your dog an extra hour in the park or eat one meal that does not involve animal suffering," Ingrid Newkirk, PETA president, wrote in the tribute. 

In the name of helping animals, Simon also created a mobile veterinary clinic, a hearing dog program, provided service dogs to veterans, and he created an adoption program for shelter and rescue dogs.

Simon also bought a number of zoos and circuses just so he could free the animals. 

"Ingrid and I got this fun idea. I started to buy these zoos and circuses in December. I just wanted to have some days where I get to see animals walk in grass for the first time," Simon once told Hollywood Reporter. "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."

Simon will live in the hearts of all the animals he saved - and will continue to save with his donated fortune - forever.