"I have to have hope that it's going to be okay," Tessie Sylvester tells PEOPLE

By Caitlin Keating
June 27, 2017 12:31 PM

In the midst of raw grief, Tessie Sylvester was on the phone with a funeral director just hours after her husband John died from ALS, when her doctor called to give her devastating results from a recent biopsy.

“I clicked over and that’s when the doctor said that it was cancer and that we needed to get going with treatment,” the 36-year-old dentist and mom of two tells PEOPLE. “I sat there with [John’s body] for a second just crying. Then my parents came over and I think I just went into shock. I cried and screamed for a little bit. Mostly, I was just so scared of what was going to happen to my little boys.”

Credit: Tessie Sylvester

Fear and Hope

Since that devastating day on June 16, Sylvester, who lives in Minneapolis, Minnesota, has learned she has adenocarcinoma, a type of cancer that may affect various organs. Doctors discovered that Sylvester has a cancerous tumor on her liver. In the wake of her diagnosis, she says she can only think about how to move forward for her 6-year-old son, Gus, and 5-year-old son, Freddy.

“My biggest fear is not being there for my kids,” she says. “If I didn’t have them — if it was just me — I don’t think I would be nearly as scared.”

John and Tessie Sylvester
| Credit: Tessie Sylvester

“I have to have hope that it’s going to be okay,” says the devoted mom, who begins chemotherapy on Tuesday. “I know my boys and I don’t think they’ll care about me losing my hair as long as I’m there at the end of the day.”

Sylvester — who discovered her cancer after routine blood work came back abnormal — hasn’t told her kids about her diagnosis yet and can’t fathom how they’ll handle it.

“I’m going to wait until after the treatment and see how my body reacts and what to expect from that,” she says. “I had my hair cut really short to try and ease them into me losing my hair.”

Gus and Freddy Sylvester
| Credit: Tessie Sylvester

Later this week, she’ll try to reassure them that “mommy is getting medicine from doctors to try and help,” but it’s something they’ve been told before.

“They never understood why the doctors couldn’t help daddy,” she says of her husband, who was diagnosed with ALS in 2010. “Hopefully, I will reassure them, but even with John, my biggest thing was that I never wanted them to carry that burden. I just want them to be kids. Telling them is very daunting.”

One Day at a Time

Sylvester, who met her late husband when they both coached a youth soccer league in 2002, has had little time to grieve as she fights for her own life.

“When I go in for these scans you have to lay really still for a long time, so that’s when I’ve laid and just talked to John and cried,” she says.

Her five siblings and parents — all of whom live close by — have stepped up to help in any way they can.

“They have all stopped what they’re doing and are picking up what I can’t,” she says. “The public and strangers have been amazing as well.”

John and Gus Sylvester
| Credit: Tessie Sylvester

A GoFundMe page that was started to help with her treatment and time off from work has raised over $180,000.

“It’s not just the donations, but the people who comment and tell me stories of survivorship and send me their prayers,” she says. “It’s overwhelming and humbling.”