Family Dog 411

Is Your Dog Suddenly As Moody As Your Teen? Yep, Dogs’ Personalities Change Throughout Life, Too

Research shows that dogs go through stages and shifts with big life events, much like kids.

Originally Published: 
Research shows dogs' personalities, much like kids, change with age and big life events.
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To some people, a dog is just another animal. But for many people, dogs are part of the family; they’re the unofficial “other” siblings, the four-legged playmates, the emotional support Mom calls in for backup when she needs help cheering up a child. So, just as you’d be aware if one of your kids started acting differently, you’re going to notice if your dog seems to have a shift in behavior. And while it’s easy to overreact with worry when anyone in your household (including your fur baby) seems to be acting out of character, your dog’s sudden moodiness may very well be, well, just part of life. According to a study performed by Michigan State University, dogs — not unlike children — will experience “profound personality changes” as they grow.

You probably saw this firsthand when you brought a second puppy home. Or maybe you witnessed it as your one-and-only doggo aged from a happy, perky pup to a slower, more sullen senior dog. Even cats, known for being aloof, will show an altered personality each time you bring home a new feline addition. But it isn’t just normal life events or the gradual passing of time that can alter a pet’s personality. Just as traumatic events can profoundly affect a person, dogs react to trauma in a similar way.

What is different, though, are the things dogs perceive as traumatic. For you, the new baby is a blessing. For Fido, it means less attention. When you moved your family to a new city, you were excited about the adventure. Your doggo, however, was greeted with smaller rooms, more concrete, and tons of unfamiliar smells. Knowing when your pup might be triggered, how to prep them, and how to respond to changes in your pet are all paramount to having a healthy pet-human relationship. Luckily, there are plenty of experts to guide you through the process.

When might a dog's personality change?

"Your dog's personality may change due to different factors, life experiences, and maybe even for no reason other than the passing of time," says Michelle Henry, the CEO and founder of Outdoor Dog Fun. "As a result of these changes, they may become more sympathetic, fearful, or even grumpy. Your dog also has feelings. Remember that for certain reasons — whether these have a direct relationship to you or not — your dog may feel lonely, sad, anxious, worried, or tired. And the mental imbalance suffered generates discomfort, which results in a behavior change. Any unstable and intense energy we hold can be transmitted and cause negative excitement in the dog."

According to Henry, these are the most common reasons for a dog's personality change:

  • Castration: It is very common for a personality change to occur after sterilizing your pet. We may find ourselves with a relaxed and submissive dog, or rather the opposite.
  • Old age: In old age, our dog undergoes physical and mental changes, such as the loss of some capabilities. For this reason, we may observe a change where it becomes more unsociable or passive.
  • Sexual maturity: At this stage of growth, the dog explores changes in its body. We must continue to support socialization with other pets, people and environments during this phase. It must learn to behave in this new stage of life.
  • New pet: If we add a new dog or cat to the family, it may be that our beloved dog will show some jealous behavior or dominance towards the newcomer. Although this is normal behavior, it must respect the new family member. We will put limits on the dog, though it must believe it is above (hierarchically speaking) the new pet.
  • Trauma: Sudden behavior in your dog can also stem from shocking events or extreme pain they experienced.
  • Neurological disorders: Like humans, dogs can also suffer from neural issues like brain inflammation, strokes, and brain damage, which can cause seizures, walking in circles, and lack of balance.

Other things pet parents have noticed that cause stress and personality changes for dogs: moving, new babies, and a change in ownership (even if just because one member of a couple is no longer present).

How can you help prepare your dog for big changes?

Make changes slowly.

Examples include:

  • Moving to a new home? Take them with you to visit during inspections. Or take them for walks around the new neighborhood leading up to moving day.
  • Bringing home a baby? Get them used to the new routine ahead of time. Slowly change their walking schedule to what you think it will look like with the new baby. Set up all the extra furniture and toys ahead of time and let them get used to the smell. Teach them how to behave around the new furniture. Consider practicing gentleness while you hold a baby doll. Most importantly, bring home a blanket that smells like the baby before you bring home your babe.

Talk to them about it.

Sound a little bonkers? Maybe. But, c’mon, you already talk to your dog about everything else. Even if you don't think they fully understand what you're saying, being near them, talking to them, and letting them absorb your emotions about the change will help them identify this as something you're doing together.

Take more walks.

For some humans, exercising helps them manage their stress; fortunately, the same can work for dogs. So if you and your doggo are about to go through a life-changing shift, add a few extra walks to the schedules. Not only will this help your dog release some of that nervous energy, but the extra exercise can also serve as a stress reliever for you.

Make the effort to give attention.

In your old routine with your old job, old home, or old puppy/baby-less life, your dog was used to just being the de facto outlet for all cuddles and attention. It can, therefore, be easy to not realize you might not be giving your dog as much attention as you did before the changes took place. Making sure to schedule some time or set a reminder to give attention to your OG best buddy will go a long, long way in helping your furry friend adjust.

What can you do to help your family adjust to those personality changes?

"If there are any sudden changes in your dogs' personality or behavior, it's important to first get them to a veterinarian to make sure there isn't a medical reason for the change," says Janet Cutler, Ph.D., Certified Dog Behaviorist at Senior Tail Waggers. If your dog is in pain, that could also change how they behave. So, it's ultimately important to ensure they're healthy before you immediately assume it's something else.

"Once medical reasons are ruled out, then consulting with a dog trainer or behavior professional could be helpful to see if there are changes you could help your dog through," says Cutler. "Many behavior problems and changes can be helped greatly with behavior modification, training, and management around the home. Management around your home can also help with some behavior that no longer meshes with your family. This could include keeping your dog away from certain situations, or implementing other safety measures."

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