Why the hallway layout is the problem
A cat who sits in a hallway, stares, blocks the doorway, or chases another cat away from the litter area is controlling access to a resource, even if no fight ever happens. The guarded cat learns that reaching a tray means running a gauntlet, so she delays, rushes, or finds a quieter substitute such as a bed, a rug, or a pile of clothes. Adding more trays at the far end of that same hallway does not fix anything, because the route itself is the barrier. The setup has to change so that toileting never requires permission from the guarding cat, and so that a cat already in a tray can leave by a different line than the one she entered by.
Spread trays across real territories
Place trays in at least two genuinely separate parts of the home, ideally on different sides of the guarding cat's favorite post, so each cat has a route that stays inside her own comfortable territory. Favor corners with two ways out over alcoves, cupboards, and the far end of an en suite where a cat can be cornered while she is vulnerable. Open trays help here because a hooded box has one entrance that is easy to ambush and traps the user with a single exit. Keep one tray per cat plus one extra as your count, but treat placement as the deciding factor: three well-spread trays will outperform five trays lined up beyond a guarded doorway.
Lower the tension around each location
Keep tray areas boring and predictable, with no feeding, play ambushes, or loud appliances right beside them, and avoid moving a working tray once a nervous cat has accepted it. If the guarding happens at set times, such as after meals or in the evening, scoop and refresh before those windows so nobody arrives to find the only acceptable tray already soiled. Watch body language for a week after the move: hovering in doorways, waiting until the other cat sleeps, sprinting from the tray, or leaving without burying are all early clues that one location still feels exposed. Adjust that tray a room farther away rather than scolding either cat, since punishment raises the very tension that drives guarding.
What to do if accidents continue
Continued peeing on soft items after the layout change deserves two checks in parallel. First, confirm every cat can reach a clean tray at the moment she needs one, including overnight, when doors may be closed and a hallway route disappears entirely. Second, book a veterinary check for the cat who is missing the tray if the change is sudden, if trips look strained, or if urine amounts look unusual, because pain on toileting can look exactly like a social problem and a cat in discomfort will avoid any tray that requires effort to reach. Keep a simple note of where and when accidents happen, since that pattern shows whether one route or one time of day remains unsolved.
Keeping a spread-out system cleaned
Multiple locations fail when one tray quietly becomes the forgotten one in a spare room, so list every tray, its room, and its scooping turn in one shared place. With KinsLe Care Teams you can assign each tray location to a different household member and see completed scoops timestamped, which keeps the guarded cat's former hallway from creeping back as the only tended spot.