Teddi Mellencamp has a lot on her mind as she battles stage 4 cancer.

Her skin melanoma has metastasized to her brain and lungs causing tumors in both organs.

In a recent Instagram Stories post, the former Real Housewives of Beverly Hills cast member, aged 43, opened up about her health journey as she walked on a treadmill.

While exercising and clad in a white sports bra with matching leggings, she expressed gratitude for being able to be active, even though she expressed a preference for running.

‘Sometimes kids say things that really put things into perspective,’ she said. 

During the session, she shared an endearing moment involving her child, Cruz, reassuring her about her concerns regarding a scar on her head following a recent brain surgery.

Teddi is mom to daughters Slate, 12, and Dove, five, and son Cruz, 10, with estranged husband Edward Arroyave. 

‘True, I mean I didn’t know what rizz was, but I learned,’ she added. 

‘It’s good, I’m a huge dork enjoying my walk. Have a great day guys,’ her video concluded. 

Teddi’s battle with brain cancer has taken a further devastating turn – with the reality star said to be preparing her children ‘for the worst.’

The daughter of rocker John Mellencamp previously said she felt she was on her ‘deathbed,’ has already undergone more than 20 surgeries during her two and a half year cancer battle.

She was initially diagnosed with melanoma but now it has spread and she recently underwent surgery to remove four tumors from her brain.

Last month, more tumors were discovered in her brain and lungs which has caused Teddi to face the reality that her kids may have to face life without her in the very near future.

‘Teddi is a fighter – anyone who has watched Real Housewives can attest to that,’ Radar reported.

‘But it just saps her fighting spirit to think she had beaten this, only to receive another horrible diagnosis. 

She has told her children that mommy’s sick, but she is going to be okay, and now it’s tearing her up to lay out the dark truth to them.

‘Teddi does her very best to remain optimistic through her ordeals, but her main thought is with her family and beating this cancer for their sake.’

The outlet reported that oncologist Dr. Jerome Spunberg said Teddi ‘faces a grim future of painful treatments and likely a tragic end.’

Spunberg has not treated Teddi’s cancer, but her said, ‘Melanoma is just notorious for spreading, and more times than not, more tumors pop up even as doctors treat the existing ones.

‘She’s likely facing a period of very serious and painful medical ordeals, and the cure rate, unfortunately, is very low.’

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In February she publicly shared that doctors discovered multiple brain tumors, resulting in emergency surgery.

The effects of the growing tumors were present for six months before the star finally sought medical attention. 

She’d been suffering from migraines but ignored the pain and kept moving forward as she faced other issues in her life, Teddi said earlier this month on her Two Ts in a Pod podcast with Tamra Judge.

‘I didn’t want to face any of it. And I was like, I just need to keep moving forward. And if I keep moving forward, then everything’s going to be fine,’ she explained about her mindset at the time.

The former Real Housewives of Beverly Hills star then detailed her difficult recovery as she spoke about being discharged from the hospital after her February 12th brain operation.