Sudden Behavior Problem with Brother/Sister Coons

We have two Maine Coon cats from the same litter; a brother (neutered) and sister (spayed). They've been great companions for over a year since we got them from the breeder. They are both house cats with little regard to going outdoors. However, the male did venture away on Sunday morning when the front door was left ajar. Several hours later he showed up on the opposite side of the window looking at his sister as if to ask her to let him indoors; like a sailor coming off a night of liberty. He was filthy, having been in our wood behind our home, so we promptly bathed him. Since his return and after the bathing (and for two days going...) the female sister has begun 'hissing' and vocalizing as if to attack. She avoids him and he looks at her as if he doesn't understand the rub! Though funny at times, it has become a concern. Does anyone know why this odd behavior by the female has begun and persists. It's as if she's forgotten who her brother and pal was and is dealing with a stranger! Stumped in Indiana

He smells different, pour some vanilla extract on a towel then rub both cats down so they smell the same.
This is a common problem when one cat got to the Vets office.

yup, its the smell thats done it :smile:

you could try just rubbing the boy with a blanket that both cats have slept on. or rubbing a clean towel allover your girl (especially her face, to obtain scent from her facial scent glands) then rub it over the boy.

it should settle down in time, but be warned, in some cases, the relationship is never quite the same again.

good luck