MESQUITE – You might have seen the post on Facebook, Twitter or Instagram: photos of a teenage girl and her mom from the first and last day of every school year until her senior year - when she lost her mom to cancer.

Her name is Savannah Inthalangsy. She graduates from Mesquite’s John Horn High School on Saturday.

So many things stood out to Savannah about her mother Phelana Foster’s battle with cancer, but perhaps she’ll remember most that her mother never stopped smiling – not at chemo, not when she lost her hair. Never, said Savannah.

“All throughout her cancer, she didn’t really cry or get upset in front of other people about it,” she said.

On every first and last day of Savannah’s high school career, she and her mother went for ice cream or Starbucks and took a picture. On Savannah’s phone are photos of the first and last day of her freshman, sophomore and junior years and the day she started her senior year.

But the photo of the final day of senior year is different.

Savannah is smiling at her mother’s graveside, a Starbucks up in her hand and another sitting on her mother’s headstone.

“I wanted to finish off the tradition,” Savannah explained. “I would always say we’re best friends and she’d say, ‘We’re not friends! I’m your mom. I can’t be friends with you!’ But I still think we were best friends.”

Foster died on December 19, 2017 after a seven-year battle with ovarian cancer.

When Savannah tweeted a collage of the photos, the post went viral.

“114,000 retweets and 578,000 likes,” she said on Friday morning, looking at her phone. “I feel really supported. It boosted me.”

Each of those numbers has risen by thousands since WFAA spoke to her.

She said she doesn’t know how or why the post went viral, but she’s happy it did.

“She’d probably joke around about being famous,” she said about her mother, who “posted on Facebook almost every day.”

Savannah plans take the summer off and then plans to attend Eastfield College in the fall, eventually transferring to the University of North Texas at Dallas. Her mother was a preschool teacher. Savannah wants to be a teacher, too. She is bravely facing her future the way her mother faced down cancer.

Savannah believes she is a lot like her mother, especially when it comes to staying strong in the face of adversity. She teared up slightly when talking about visiting her mother’s grave – a rare crack in a tough exterior.

“It didn’t feel like school was coming to an end but I think tomorrow it’s going to hit and I’m going to probably be a little emotional,” she said with a laugh.

Next weekend, her family is hosting a party, following the plans set in place by her mother before her death.