New York, New York - Alissa Moulster and her partner recently fostered some kittens, and their cat Martini seemed mostly indifferent to the babies – until they had to leave!

Alissa has often taken in little foundlings from animal shelters until they finally find a permanent home with other families.

However, the New Yorker was not prepared for what happened this time when the fosters were relinquished.

For two weeks, Alissa had been caring for the baby cats Phoebe and Joey, who came to her at just six weeks old.

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As the kittens were separated from their mother far too early, they still needed a lot of care and support from their temporary family.

Thanks to Alissa's tireless efforts and experience, the two siblings developed beautifully and were eventually rehomed.

While she herself was prepared to say goodbye to the two sweet kittens, Martini found it anything but easy.

Just how attached Martini was to the foster kittens became apparent on the day that they moved out.

"We knew she enjoyed hanging out with them or found them fascinating, but as we were headed out the door to give the kittens to their adoptive family, Martini kept jumping up on the cat carrier and pulling the kittens down," Alissa told Newsweek.

Every time Alissa's partner lifted the carrier with the two animals, Martini would pull them back down with her claws, preventing the couple from leaving the apartment.

Alissa was heartbroken to see Martini so sad to say goodbye to the kittens.

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In a video she made of the moment, the pet owner can be seen in tears.

"It also made me happy because I saw how much love she had and that she wanted to protect these little babies," she added.

Even after the foster animals left, Alissa says you can still tell that Martini misses the babies. Every time the front door opens, the cat runs towards it excitedly – almost as if she were expecting Phoebe and Joey to return.

"My heart is aching," admits Alissa in the video. "Why did I think I was strong enough to do this?"