For many families, pets are never “just animals” — they are companions, siblings, and part of the everyday rhythm of home. When one pet passes away, it’s common for owners to notice a change in the behaviour of the pets left behind. They may seem quieter, restless, withdrawn, or spend time searching the house.

It often leaves families wondering: do pets know when another pet has died?

While we can’t ask them directly, science suggests that animals are highly sensitive to pheromones, scent changes, and emotional cues, all of which can play a role in how they perceive loss.

The Role of Scent and Pheromones

Pets, particularly dogs and cats, experience the world far more through smell than humans do. A dog’s sense of smell, for example, is estimated to be tens of thousands of times stronger than ours.

Animals constantly communicate through pheromones — chemical signals that carry information about identity, health, stress, and emotional state.

When a pet becomes seriously ill or passes away, subtle changes occur in the body. These changes can alter scent signals that other animals in the home may detect. In some cases, pets may sense that something is different long before their human family does.

This may explain why some animals stay close to a companion that is unwell, or behave differently in the days leading up to a loss.

Do Pets Grieve?

Many vets and behaviourists believe that animals do experience a form of grief or loss, although it may not look the same as human grief.

After losing a companion, some pets may:

• Search around the house or garden
• Sleep more than usual
• Lose interest in food or play
• Become clingy with their owners
• Seem quieter or withdrawn

Others may appear relatively unchanged. Just like people, every animal responds differently.

Should Pets See Their Companion After They Pass?

Some behaviourists suggest that allowing a pet to see or smell their companion after death can help them understand what has happened.

Animals rely heavily on scent for recognition. Being able to investigate their companion can sometimes reduce confusion and searching behaviour afterwards.

However, this isn’t right for every situation or every pet. Some animals may show little interest, while others may prefer distance.

Owners should trust their instincts and what feels most appropriate for their pet.

Families often ask us about this, and there is no single “correct” answer — only what feels right for both the family and their pets.

Helping a Pet Who Has Lost a Companion

If your pet seems unsettled after losing a companion, there are gentle ways you can help them adjust.

Maintain familiar routines
Animals find comfort in predictability. Keeping feeding, walking, and bedtime routines the same can help them feel secure.

Offer extra attention
Some pets may seek more closeness with their owners after a loss. Spending a little extra time with them can be reassuring.

Encourage gentle activity
Walks, play, or enrichment toys can help lift mood and provide positive stimulation.

Be patient
Some pets settle within a few days, while others may take several weeks to fully adjust.

If a pet stops eating for more than a day or two, or seems persistently distressed, a conversation with your vet may be helpful.

The Bond Between Pets

When pets share a home, they share far more than space. They share routines, smells, companionship, and often deep bonds.

For the pet left behind, the absence of that familiar presence can be just as noticeable as it is for the humans who loved them both.

Understanding that pets may sense and respond to loss can help families offer a little extra comfort during an already difficult time.

And in doing so, we honour the quiet, loyal relationships that exist between the animals who share our lives.