A hallway is a perfect ambush spot for a cat, and when one cat sits there staring, loafing, or rushing out as the other passes, the trays beyond that hallway effectively disappear for the shyer cat. She does not stop needing the litter tray — she stops risking the trip. That is why the problems in this setup look like litter problems but start as an access problem, and why cleaning the trays harder without changing the route rarely solves anything.
The accidents this guarding pattern creates
The cat who is being blocked usually shows one of three patterns. She may urinate just short of the hallway — on a rug, laundry pile, or corner of the room she feels safe in — because she waited and then could not wait longer. She may hold on for long stretches, then go in a rushed visit where she perches on the tray edge, does not dig or cover, and bolts out before the guarder notices her. Or she may yowl near the hallway, pace, and abandon the attempt altogether.
Step one: create a tray route that bypasses the hallway entirely
Do not start by scolding or moving the guarding cat; start by making his post irrelevant. Place a second tray — ideally one tray per cat plus one extra in total — in a quiet room on the blocked cat's side of the home, somewhere she already rests and can reach without crossing the hallway. Keep the litter type and depth the same as the tray she already accepts so location is the only new variable. Leave a clear escape path from that new tray, with no dead-end cornering, and keep doors on that route propped open during the first days so she never meets a shut door and a waiting cat at the same moment.
Step two: lower the value of the hallway post
Once the backup tray exists, make the hallway itself less rewarding to hold. Remove food, play, and cosy bedding from that stretch so it stops being a territory worth defending, and give the guarding cat his own attractive resting and play spots in another room. Run short play sessions for him away from the hallway, ending before the other cat's usual tray times, so his energy is spent elsewhere. If you see him settling into the guarding spot, redirect calmly with a toy dragged away from the corridor rather than picking him up and carrying him past the other cat, which can turn a stare-down into a fight.
Step three: rebuild the blocked cat's confidence at her new tray
Show her the new tray when the house is calm, let her sniff and step in without being followed, and praise quietly if she uses it, without hovering. Scoop that tray promptly — a cat who has been ambushed will abandon a backup tray quickly if it smells used or if she must linger digging in dirty litter. For the first week, note when she uses it and whether hallway incidents continue; that pattern tells you if the tray needs moving closer to her sleeping spot.
When the hallway problem needs a vet or behaviour check
See a veterinarian promptly if the blocked cat is straining, crying in the tray, passing only tiny amounts of urine, or has blood in her urine — being unable to reach a tray comfortably can mask or worsen a painful urinary problem, and a male cat who cannot urinate at all is an emergency. If both cats are medically clear but ambushes escalate to biting or one cat stops eating, ask your vet about a referral for behaviour help rather than adding more trays indefinitely. KinsLe Care Teams helps you keep this plan consistent by assigning the morning and evening tray checks for each cat to specific family members, with completed tasks timestamped so a missed scoop on the backup tray never goes unnoticed.