Dog Grieves for 21-Year-Old Owner Killed in Car Crash: 'It's as If He's Looking for Someone'

(INSIDE EDITION) A dog is seen mourning the loss of his owner in a heart-wrenching photo after the man was killed in a car crash.

Abraham Martinez, who was from California, was sitting in his car in a parking lot on May 10 when he was rear-ended. The accident sent Martinez's car flying into oncoming traffic, and he was hit by a truck and ejected from the vehicle.

Since his passing, Martinez's 1-year-old dog Jax has not been himself,terribly missing his owner. In a heartbreaking photo posted by his sister, Cassandra, the dog lies beneath a memorial to Martinez.

"Jax began to mope around the house and just sleep. It's as if he's looking for someone and is disappointed," Martinez's sister, Alexandra, told InsideEdition.com.

"It is still something we can't understand and find it so hard to accept. We are trying to take everyday minute by minute because that's all we can do right now," she said.

When she saw the photo of Jax beneath the memorial, she said, "It made us all sad. We realized that not only are we all heartbroken, but so is he."

A GoFund Me page has been created to help with family expenses.

Jax was six weeks old when Abraham got the dog from his former neighbor. "From the moment we got him, they were attached," she said.

"They would sleep together. Jax was so tiny he would sleep on my top of my brother's head until he got so big that he took up the entire bed."

"Jax was my brother's and he knew it," she said.

Alexandra said her brother "was the one individual in our family that any of us could always count on. He was our family's go-to guy and he never let us down."

"My family is very close and it is going to be incredibly hard to fill this void in each of our lives, individually and as a whole," she said.

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