Keep a Shih Tzu introduction at ground level
A Shih Tzu meeting a resident pet for the first time should stay on the floor, where the little dog can move away under his own power. Owners instinctively scoop a small dog up when a bigger resident animal approaches, but a Shih Tzu held in arms has lost every option except barking or snapping, and being presented from above can also trigger a resident dog to jump up at the dangling newcomer. Place the Shih Tzu behind a low gate instead, in a pen or roomy area with a bed, water, and a hiding nook, and let the resident pet investigate from the other side.
Watch breathing and heat during Shih Tzu sessions
A Shih Tzu has a short muzzle, and excitement, warm rooms, and sustained barking all make breathing noticeably noisier and harder for this breed. Run introduction sessions in a cool room, keep them brief, and end them while the Shih Tzu is still breathing comfortably rather than snorting and panting from stimulation. A resident pet introduction is emotional exercise even when the Shih Tzu barely moves, so treat a few quiet minutes as a full session for a dog who is panting hard.
Let the resident pet choose the distance
Resident animals accept a Shih Tzu more readily when they control how close they come, because a small, mostly stationary newcomer behind a barrier is easy to assess and easy to leave. Reward the resident pet for calm curiosity near the gate and equally for choosing to walk away, since an animal free to disengage rarely feels the need to drive the newcomer off. Never carry the Shih Tzu over to a resting resident pet for a closer look, and never place the Shih Tzu on the resident's favorite chair or bed to see what happens.
Handle grooming smells and coat carefully around the resident
A Shih Tzu's long coat holds scent strongly, and a freshly groomed dog returning with perfumed shampoo can smell like a stranger to a resident pet who had just accepted him. Keep grooming products mild and consistent during the introduction period, and avoid scheduling the first meetings for the hours right after a bath or a salon visit. Brush the Shih Tzu in a neutral room rather than beside the resident pet's bed, so loose hair and grooming fuss do not become part of the resident's territory.
Fold the Shih Tzu into household life in small pieces
Add shared experiences one at a time: resting in the same room, then being in the garden together with the Shih Tzu on a light harness, then relaxed evenings with both animals settled near their people. Keep feeding completely separate until coexistence is well established, since a Shih Tzu eats slowly and a resident pet finishing first will inevitably hover. Separate sleeping arrangements stay in place at night, when nobody can supervise and a startled reaction in the dark can undo weeks of careful gate work.
Ask every family member to greet the resident pet first sometimes, not always rushing to the appealing new arrival, because resident animals notice exactly where attention has moved. A household rota written down, covering gate sessions, separate feeds, and one-on-one time with the resident, stops goodwill from depending on memory, and KinsLe Care Teams keeps that Shih Tzu rota visible with each duty claimed by a person and ticked off when finished.