A San Marcos couple found dead after an alleged arson fire at their home is being remembered by their children as family-centered grandparents and parents whose “warmth was felt by everyone they met.”

Michael and Kathy Austin were discovered late Saturday inside their burning home on Lacebark Street near Borden Road as firefighters searched a room on the second floor.

Their tenant, Luis Alvarado, 33, was later arrested on suspicion of murder, arson and resisting an officer, sheriff’s officials said.

He is expected to be arraigned Thursday in Vista Superior Court and is being held without bail.

Although not yet identified by the county Medical Examiner’s Office, the couple was named in a GoFundMe page created by their family on Tuesday.

In the fundraiser, organized by son Gabriel Austin, family members said they were mourning “two incredible people who still had so much life left to live.” It said the two, lovingly called “Poppy” and “Grandma” within the family, were “truly one of a kind—loving, compassionate, and endlessly generous.”

“They didn’t just talk about kindness; they lived it every single day.”

The money generated by the fundraiser will be used to help cover funeral expenses and the rebuilding of the home, the family said.

Within the first few hours of the campaign, more than 140 people pledged more than $18,000.

Included with the post is a family photo of 20 people — young children and adults smiling and making silly faces.

“They led by example, teaching all of us that grace, understanding, and love matter in every moment,” Gabriel Austin wrote. “Their warmth could be felt by everyone they met, and their impact on the people around them will last forever.”

Michael Austin was described as having an eclectic palette, who was always cooking new foods and insisting others try them. He was also recalled as a storyteller whose “personality filled every room.”

“People naturally loved being around him,” the post said.

Kathy Austin was described as having a “goofy silly personality” who enjoyed bowling and doing arts and crafts with her grandchildren.

“The amount of kindness, grace, and forgiveness our mom showed to everyone was truly remarkable. She always seemed to know the right thing to say, no matter the situation,” the post reads. “Grandma was home, no matter where you were. She was our safe place — the person we could always run to, no matter what.”

The couple’s dog, Journey, also was lost in the fire, according to the family.

Sheriff’s officials have not released the cause or manner of how the couple died. Investigators also have not released a motive for the fire.

According to homicide Lt. Juan Marquez, Alvarado was a tenant who had lived at the home.  He was detained at the scene the night of the fire and later arrested by detectives. No other information has been released.