Lauren has publicly shared that Sandra was misdiagnosed with and treated for cramps, IBS and muscle issues.
The cancer still remained undiagnosed as it spread to her hips.
Sandra was 38 years old when she became unwell, and passed away at age 41, which seems tragically young.
Making the diagnosis all the more difficult was the fact Sandra had no family history of the disease.
Lauren has been very open about the pain of her loss, often taking to Instagram to share photos of her sister-in-law and discuss bowel cancer in an attempt to raise awareness.
“The symptoms are not obvious…” the mum-of-two began an Instagram post today.
“Friends – no matter how minor your symptom is, get a second opinion, get all the tests – do not feel embarrassed or ‘over the top!
“If she had been AWARE that Bowel Cancer affects young people, or knew of someone’s story, she may have done a test and may have been able to beat it & survive. But it was detected too late for our darling Sandy, and left too long untreated. Awareness could have saved Sandy’s life,” she wrote.
“PLEASE GENERATE AS MUCH AWARENESS AS POSSIBLE 🙏🏼,” she finished, all in caps.
The A Current Affair interview airs on Channel Nine at 7pm on Monday night.