John Mellencamp gave a rare update on his daughter Teddi Mellencamp's health as she battles stage 4 cancer. "It's not f***ing fun," John, 74, said of Teddi's cancer journey during the Wednesday, January 14, episode of the "Joe Rogan Experience" podcast. "She's got cancer in the brain, and she's suffering right now." The "Jack & Diane" singer noted that Teddi, 44, is "really sick" after being diagnosed with stage 4 brain cancer in early 2025 following a battle with melanoma in 2022. John, who has five children - he shares daughter Michelle, 55, with ex-wife Priscilla Esterline, daughters Teddi and Justice, 40, with ex-wife Victoria Granucci, and sons Hud, 31, and Speck, 30, with ex-wife Elaine Irwin - also opened up about what Teddi was like as a child. Teddi Mellencamp and Father John Mellencamp's Quotes About Their Bond "That kid used to call me up and I'd go, 'Teddi, you can have a thought without asking me if it's ... you know, figure it out yourself,'" the musician recalled, letting out a little laugh. "You don't have to ask me everything, you know?" While John remembered Teddi calling him for advice as a kid, he noted that it wasn't always smooth sailing raising his family - especially the girls. "Girls, at about 12, you lose them and then about 21 they come back," he explained. "I kinda lost mine." Teddi Mellencamp. Phillip Faraone/Getty Images for The Recording Academy While both Teddi and John have admitted their relationship was strained at times, John has been by his daughter's side every step of the way when it comes to her cancer battle. "He has been beyond," Teddi said of her father during a July 2025 appearance on "The Jamie Kern Lima Show" podcast. "The things that I wouldn't be capable of doing without my dad - not only for financial reasons." Teddi was diagnosed in 2022 with melanoma. In February 2025, she announced she had stage 4 melanoma that had metastasized to her lungs and brain. Teddi Mellencamp Has 4 More Brain Tumors: Inside Her Cancer Battle The Real Housewives of Beverly Hills alum has since undergone surgeries to remove several tumors. Teddi explained that in summer 2025 she was pressing pause on her immunotherapy treatments after it took a toll on her physical health. Through all the ups and downs, Teddi has leaned on her dad for support, telling podcast listeners in July 2025 that with all the medical treatments "he has stepped in." Teddi Mellencamp. Courtesy of Teddi Mellencamp/Instagram She noted on "The Jamie Kern Lima Show" that John "helped me have a nurse" and that her dad "calls me every single day" to make sure "that I'm OK." In October 2025, Teddi gave her father a shout-out on social media for sticking by her amid the tough time. "It's been 10 months since my brain surgery and I am so grateful to @johnmellencamp for continuously being there for me and my family the entire time," Teddi wrote via Instagram at the time, sharing a photo of the singer and her two daughters, Slate and Dove. (Teddi shares Slate, 12, Dove, 5, and son Cruz, 11, with estranged husband Edwin Arroyave.) Teddi joked, "Although apparently now that I'm no evidence of disease I can take photos without myself in it so I guess we're all healing 🤣. Love you so much, Cougs. Thank you for everything ❤️."