It's hard to know what goes through a cat's mind, but aggressive or pouting behavior could be a sign of jealousy. Here's a guide to recognizing, understanding, and preventing the green-eyed monster from showing up in your household.

If cats suddenly get very possessive and grumpy in the presence of a new family member or pet, many owners suspect the problem is jealousy.

And it's true, jealousy is a common phenomenon in the animal kingdom.

Whether cats become jealous and how it manifests itself depends on a variety of factors. Jealousy is an individual thing for non-humans too and everyone reacts differently.

Cats Cat owner is shocked to see his pet on a cliff!

Not every cat gets jealous. But those who don't like sharing or feel insecure about their position often express these negative emotions.

A particularly tasty treat, permission to sleep on the bed, cuddling with their loved ones, or their daily playtime are all perks that cats fear they could lose.

So what makes a normally friendly feline go into a scratchy sulk?

As with their owners, there can be many triggers.

These are some of the most common:

Cats Cat has hilarious reaction to his own reflection!

• a new cat in the house
• other pets, like dogs
• a new life partner
• a baby

The most frequent cause of cat jealousy is usually a new pet in the home, but even a new life partner or a baby and the changes that come with them can be very stressful for cats.

If this "intruder" is now the center of attention, the familiar social fabric that the cat depends on suddenly unravels.

But cats aren't just jealous of other creatures.

Computers, television sets, cell phones or books - anything that takes a human's focus away can make a cat battle fiercely to win it back.

The typical habit of lying on the keyboard is more playful than anything else, but it still shows how sensitive some fur balls are to no longer being in the spotlight.

Every cat expresses jealousy in its own way.

In most cases, however, it's a major change in normal behavior.

A cat's particular temperament and character determine how it reacts to being unhappy.

Some cats wear their jealousy on their sleeve: they stop cleaning themselves and even stage messy protests on the carpet.

They can also become aggressive and take sneaky swipes at a new housemate when nobody is looking, while others express their anger openly by scratching, biting, and hissing.

But not all cats are this obvious.

It is more difficult to detect jealousy in cats that just let their feelings eat away at them. They suffer silently, retreat to a corner of the room and sulk, or repeatedly refuse to feed. Some can start to shed or no longer want to be stroked or snuggled. Even staring intensely at a new pet can be a sign of jealousy.

Dealing with these fragile personalities can be hard. A cat that is by its very nature introverted is easily overlooked and neglected.

Here are the various signs of jealousy summarized again:

Signs that a cat is jealous

• destructive tendencies
  
• aggressive behavior towards people and animals
• decline in hygiene and urinating or defecating on objects
• refusing to feed and weight loss
• indifference
• sudden intrusive behavior
• sudden compulsive behavior

But watch out: All these signs and changes can also indicate a serious disorder. If you notice a sudden shift in character, you should have your cat checked by a vet!

Multiple cats in the same household can get jealous of each other and this shouldn't be taken lightly.

It's perfectly normal for new housemates to need some time before they can become buddies. But if things still haven't improved after several weeks, they need some help to settle their differences. Permanent tension, intense staring, or puffed up fur are clear signs of aggression.

How to fix this

If jealousy is involved, patience, trust and training are the path to a good relationship.

Consistency is very important to cats - whatever is forbidden for one should apply to the other as well. Hierarchies also play a role: always greet the older cat first when you come home and give it first dibs on food and treats.

If tension is building, it often helps to distract the cats with games. Something as small as a loose string can be very effective at de-escalating. Even a loud clap of the hands can be enough to stop a confrontation and calm them down.

Sometimes, doing nothing at all and ignoring your four-legged friends is the best course of action.

The ideal case is of course avoiding the presence of jealousy altogether.

In most cases, a cat's body language contains enough hints that something negative is brewing.

If the fur ball you're currently petting is getting dirty looks from the other one, it's best to share the love to show that there's no preferential treatment involved.

Other ways to prevent jealous feelings:

• setting up plenty of sleeping spots, feeding areas, and providing toys
  
• personal one-on-one time with each cat every day
• taking account of the individual needs of each cat
• enforcing general rules that apply equally to all cats

Most cats will display jealous behavior at one point or another. However, some are particularly sensitive. In these cases, a new pet or human in the house is just the trigger, not the root cause of the problem.

In general, a confident cat that gets enough attention and care from its owner is less likely to get jealous than a cat that is insecure, introverted, fearful, or marked by bad experiences.

Cats that have long been used to living alone with their beloved humans will find it more difficult to share that attention. Issues around food can also lead to increased competition.

In these cases, it's essential to show some understanding for these fears and insecurities, and to always react with love and consistency.

After all, what could be more human than jealousy?