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Littermate Syndrome

Littermate syndrome, also known as "sibling syndrome" or "sibling aggression," is a behavioral issue that can occur when two puppies from the same litter are raised together in the same household. It typically arises when these puppies are adopted or acquired as a pair and spend a significant amount of time together without enough individual socialization and training with humans and other dogs. While it's not guaranteed to happen in every case, the risk of littermate syndrome is something that prospective dog owners should be aware of.

The main factors contributing to littermate syndrome include:

  1. Lack of Individual Bonding: Puppies raised together may become overly dependent on each other, forming an intensely close bond that can lead to separation anxiety when separated. This bond might hinder their ability to build strong connections with humans and can make training and socialization more challenging.

  2. Insufficient Socialization: When puppies spend most of their time with each other, they may not get adequate exposure to different people, places, and other dogs. This lack of socialization can result in fear, anxiety, or aggression towards unfamiliar situations or individuals.

  3. Competition for Resources: Siblings can sometimes develop a competitive dynamic, especially if they are not taught proper boundaries and sharing early on. This can lead to conflicts over food, toys, attention, and other resources.

  4. Limited Obedience Training: Training two puppies simultaneously can be more demanding and requires individualized attention. Without proper training, both puppies may struggle to understand and follow basic commands, leading to unruly behavior.

Signs of littermate syndrome may include increased anxiety when separated, heightened aggression towards outsiders (including other dogs), difficulty following commands, and an inability to cope independently. Additionally, the bond between the littermates may be so strong that they become disinterested in forming relationships with other dogs or people.

It is important to note, dogs do not necessarily have to be from the same litter to suffer from littermate syndrome. If you acquire dogs at the same time, there is the potential for the same outcome.

It is recommended to get one dog at a time, train it to be the dog you want it to be before adding a second dog. Bringing a new dog into the family does not correct the bad behaviors of the first dog. In many cases, it makes it worse.

As always, we are happy to answer any questions you may have!


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