Vallejo, California - When Maria Long saw a plastic bag lying on the sidewalk, she had a bad feeling. Then she heard a cat's meow.

"I was thinking maybe it was a cat in a tree… I was like, 'I hear the cats, I just don’t know where they are,'" Long said.

When Maria Long from Vallejo in California recently saw a plastic trash bag lying on the sidewalk, she had a bad feeling.

"It started moving, and I was like, ‘Oh, heck no. Those are the cats,'" Long said.

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When she looked inside, Long was struck by a shock: four little baby cats, just a few days old, were in dire need.

“[I]t was during the end of the heat wave that we had here... It was directly under the sun on the sidewalk, no trees or anything," said the Californian, according to a recent report by The Dodo.

She immediately took the four to the Humane Society of the North Bay.

Luckily, the shelter was only a few minutes away, and Long was relieved to see that the staff there were sure the kittens were fine after an initial examination.

"They probably were just mostly traumatized and shocked," Long explained the desperate meowing of the little animals.

But the story didn't end there, because the next turning point for the cat rescuer was just around the corner.

The Instagram video, which went viral, shows the story of the four foundlings.

In the caption next to it, the woman writes that she could never have imagined being a foster mom for cats.

But that day changed: Long took all four furry friends home with her, feeding and caring for them as best she could.

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"I never felt more like a mom than when I was fostering them," she said fondly.

However, she has since returned the little ones to the animal shelter, where they have been placed with longer-term foster families. They will have to wait a few more weeks until the cats are big enough to be put up for adoption.