Tarek's estranged wife Christina also shared her support of their co-star and friend, Frank Miller.
Tarek and Christina El Moussa are putting their differences aside to help a dear friend.
The contentious exes have teamed up to raise money for Frank Miller, a contractor on Flip or Flop who is battling two forms of cancer.
Tarek, 35, and Christina, 33, took to social media on Monday to ask fans for their help and donate anything they could to Miller's GoFundMe page.
"PLEASE PLEASE WE NEED YOUR HELP TO SAVE A LIFE!!! Our contractor Frank Miller from Flip or Flop is battling 2 very, very aggressive cancers, really bad ones, he's fighting for his life out of feeding tubes!!" Tarek wrote on Instagram. "His medical bills have become unattainable and we need your help to try and save Frank's life.... any donation helps whether its $1 or $100 dollars anything will help this amazing man. We love him so much that Christina and I our donating $5,000.00 to his GoFundMe account to start it. Please click on the link and please donate something anything to help this amazing man stay alive. FRANK WE ❤️❤️❤️❤️❤️ you so much buddy. Click the link in my bio and help save this wonderful man! It's right below my name on my main IG page."
Meanwhile, Christina wrote: "Our contractor, Frank Miller, from #fliporflop is battling two very serious forms of cancer and his medical bills are becoming unbearable. Please click the link in my bio and donate... every little bit helps. Thank you from Tarek, Frank and I."
The reality star later deleted her post, but continued to promote Miller's GoFundme account in her Instagram profile.
Miller's GoFundMe has a goal of $50,000 and, at the time of publishing, has raised over $15,900.
Tarek has his own history of battling cancer. In February, the reality star revealed that he was diagnosed with testicular cancer around the same time he discovered that he had thyroid cancer in 2013.
"Getting the thyroid cancer was hard enough, and then a few weeks later, learning I had testicular cancer, I literally thought I was gonna die," Tarek told Good Morning America earlier this year. "I just didn't want to come out with it. It was more of a personal thing."
Thankfully, both cancers are in remission.
For more on Tarek's battle with cancer and why he decided to speak out, watch below.