Two cats brother and sister from the same litter, spayed/neutered overall get on well.
Boy cat has been off on a wander wasn't here Sunday or last night came home v early this morning when dp went out to work about 4am. Usually he's in every night. Girl cat is now hissing and growling at him, he's ignoring it completely. She has done this before when he once went for a couple of days previously according to dp but not sure how long it lasted (I didn't actually see as I was at work).
Is this normal?