Adopting a pet: the first days at home
How to prepare your home, which supplies you need, how the 3-3-3 rule works, and how to introduce the new arrival to children and other pets. Step by step.
Gatsou Team
· 7 min read
Adoption is one of life's best moments — and one of the most decisive for the relationship you'll build. The first weeks lay the foundations: trust, routine, safety. Here's how to organize them properly, from preparing your home to the moment your new family member finally feels "at home".
Before they come home
1
Pet-proof the house room by room
Tidy away cables and small objects, secure balconies and windows with screens (critical for cats), and remove toxic plants — lilies, for example, are extremely toxic to cats.
2
Gather supplies in advance
On arrival day you don't want to be running to the shops — everything should be in place before the animal walks in.
3
Agree as a household
Who feeds, who walks, what are the rules (couch yes or no?). Consistency from day one makes settling in far easier.
4
Set up a "safe room"
A quiet space with their bed, water and toys, where they'll spend the first days before exploring the whole house.
What you'll need
•
Food and water bowls — ideally stainless steel or ceramic
•
A comfortable bed or blanket
•
Collar with ID tag and leash (dog) / carrier (cat and dog)
•
Litter, litter box and scratching post for cats
•
Toys and chew items for release
•
The food they were already eating — changes happen gradually
The first week, step by step
1
Book a vet appointment
A general check-up within the first 3-5 days confirms their health, completes vaccinations and checks the microchip.
2
Sort out the microchip
Transfer or register the chip under your details in the National Registry — so if they get lost, they come back to you.
3
Build a steady routine
Meals, walks and sleep at consistent times. Predictability is the strongest "calming aid" for an animal in a new environment.
4
Let them set the pace
Don't push for cuddles and hugs. Let them approach you on their own — trust can't be rushed.
The 3-3-3 rule
3 days — 3 weeks — 3 months
3 days to decompress from the change, 3 weeks to learn your routine, 3 months to truly feel at home.
The 3-3-3 rule is a guide, not a law: some animals settle in days, others — especially those with a rough past — need longer. If in the first three days your pet hides, eats without appetite or avoids you, don't be discouraged. That's the normal decompression stage, not a sign they "don't like you".
Introductions to children and other pets
With children: explain in advance that the new arrival needs quiet in the first days — no chasing, no tight hugs, no disturbing them while they eat or sleep. With other pets: keep spaces separate at first, let them get to know each other's scent (a blanket works wonders), and keep the first meetings short and supervised. Rushing this step is the most common reason things "don't work out".
Don't switch their food abruptly — moving stress plus new food is a recipe for stomach upsets. Keep whatever they were eating and transition gradually over 7-10 days.
When to call your vet
•
Not eating or drinking for more than 24 hours
•
Severe lethargy, constant hiding, or fear-based aggression that doesn't ease
•
Vomiting, diarrhea, coughing, or discharge from the eyes or nose
•
Any sudden behavior change after the first days
Frequently asked
What is the 3-3-3 rule for adopted pets?
It's a practical guide to adjustment time: roughly 3 days for the animal to decompress, 3 weeks to learn your routine, and 3 months to truly feel at home. Every animal has its own pace.
How soon should I take my newly adopted pet to the vet?
Book a check-up within the first 3-5 days. The vet will confirm their health, complete vaccinations and deworming, and check or transfer the microchip.
What supplies do I need before bringing a pet home?
The basics: food and water bowls, a bed or blanket, a collar with ID tag and leash or a carrier, litter and a litter box for cats, a few toys — and the food they were already eating.
How do I introduce the new pet to my cat or dog?
Gradually: separate spaces at first, scent swapping (blankets, toys), and short supervised first meetings in a neutral space. Don't leave them alone together until you consistently see calm behavior.
Should I change their food right away?
No — keep the food they were eating and, if you want to switch, do it gradually over 7-10 days by mixing old and new. An abrupt change on top of moving stress often causes diarrhea.
When should I worry about their behavior?
If they won't eat or drink for over 24 hours, hide non-stop or show intense fear that doesn't ease after the first days, or develop symptoms like vomiting or diarrhea — call your vet.
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