Kelli Seepaul had planned to move to Toronto on Thursday, taking her two cats, Finnigan, a tabby, and Willow, a Siamese, with her.
She was about to board her plane when the airline paged her to say both cats had escaped, after ground handlers picked up their kennel and the bottom fell out of it.
Seepaul helped staff search for the animals in Vancouver airport's baggage area and Finnegan was found, but after four hours Willow was still missing and Seepaul had to fly to Toronto.
Both cats were abused before Seepaul rescued them from the Squamish SPCA in March. Now she's worried she'll never see Willow again.
"They were just leaving out food, hoping she would come out and they would catch her and I explained that you can't just pick her up and catch her because she's an abused cat," she said.
"I just don't know if they're doing enough. Their priority isn't to find my cats but it's to do other things and I just...my priority is to find my cat that they lost."
Westjet says it's doing everything it can to recover the animal and called the incident extremely rare.
In the meantime Seepaul says she's not alone in her distress - Finnegan is worried too.
"They're always together - so he's walking around the apartment calling for her."
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