A rare and aggressive cancer is taking a devastating toll on a Quebec family as two siblings fight for their lives side-by-side in hospital.

Jacob Randell, 14, and his 5-year-old sister Sophia are sharing a room at Ottawa’s Children’s Hospital of Eastern Ontario (CHEO). Their mother, Liliane Hajjar, can barely stand the sight of seeing two of her children’s names on the door.

“This is the most heartbreaking picture my eyes and heart have ever seen. I'm broken. We are all broken,” she wrote in a Facebook post on Wednesday. “This is not the life I imagined for them, but it is what it is and we will walk with them every step of the way.”

Jacob was the same age as his sister when he was diagnosed with an atypical teratoid rhabdoid tumour. Geneticists at CHEO’s Hereditary Cancer Clinic discovered it was an inherited condition caused by a mutation in the SMARCB1 gene, which can lead to highly aggressive malignant tumors in infancy.

As a precaution, the rest of the family was genetically tested. Seven-year-old Liam was negative, but Sophia tested positive. She has been monitored through regular MRI’s and ultrasounds ever since. In 2016, a brain tumour was discovered on the left side of her brain, the same location as her brother’s.

“One child diagnosed with cancer is absolutely devastating, but two is life changing,” Hajjar told CTV Ottawa last April.

Both kids had been doing well and the family felt as though they could finally breathe. Then, earlier this week, Jacob was diagnosed with kidney carcinoma, and doctors learned that Sophia’s tumor had returned.

The community has set up a GoFundMe crowdfunding campaign to assist the family with expenses. Hajjar said her family’s painful ordeal has inspired her to encourage others to spend more time together.

“You know when your kids (young and old) want to do something or ask with excitement to do something they like, and you say ‘later,’ (or) ‘maybe some other time?,’ she wrote on Facebook. “Don't wait. So many regrets of my many ‘laters’ are rushing through my brain now. So, so many regrets. I'm sorry for all my ‘maybes’ my dear beautiful children.”

With a report from CTV Ottawa’s Joanne Schnurr