At 18 years old, Angelina Anderson was known for her bubbly personality, sweetness and ability to make others laugh.

“Always kept us laughing,” Ursula, her oldest sister, who wishes to be identified only by her first name, said.

Angelina had just turned 18 this month. When she wasn’t pulling pranks or cracking jokes, Ursula said she loved to sing. The youngest of six siblings, Ursula said Angelina had high-functioning autism and touched everyone she met at school and church.

Over the last few days, Ursula has held onto memories of her younger sister after police said she was killed Sunday.

That morning, Ursula said she saw a social media post about a house fire that killed an 18-year-old in Coquina Key.

“I was just like, you know, ‘It just couldn’t possibly be.’ But I got a phone call shortly after confirming that,” she said.

St. Pete police responded to the fire on Neptune Drive SE just before 3:30 a.m. Investigators believe the fire was intentionally set, and the case is being investigated as arson.

Ursula’s 35-year-old sister, Ashley, was also at the home and taken to the hospital, where she is currently in critical condition but stable.

She said Ashley is known for being very family-oriented and, like Angelina, also smiley and happy. Ursula said Ashley is often the one who brings the family together and would give the shirt off her back to others.

Three days after the fire, Ursula said she is seeking justice and accountability for the person or people responsible.

“My sisters are very much innocent people in all this,” she said. “Nobody deserves this, and especially not them.”

Police said two other people were at the home — a teenager and a child — but were not hurt.

Ursula said she can’t fathom how someone could commit the crime. In 2011, their mother passed away, and in 2020, their grandmother also died.

“So to have this happening, it just seems unreal,” she said.

A GoFundMe has since been organized to support the family. Ursula said any penny raised would help with memorial and funeral expenses but also help Ashley rebuild after losing the home, clothing, shoes and other necessities.

“They just didn’t deserve it,” Ursula said. “If anyone knows anything, you know, who might have done this, could have done this, that you give up a name.”

St. Pete police are asking anyone with information on any suspects or unusual activity to contact the department at 727-893-7780. Any video recordings or other information the public may have is also encouraged.