What To Do With The Smallest Kitten In The Litter

One of the questions I was asked in my Q&A post was what extra support I provide for the runt of the litter. My first answer is that I don’t use the word runt.

I know what people usually mean when they say it. They mean the smallest kitten in the litter, the one that is not as big, not as round, or not growing at the same pace as the others. But I don’t like the word because it can make that kitten sound like it is less than its siblings before we have even looked properly at what is happening.

In my cattery, I talk about small kittens, kittens who are a little behind, or kittens who need more watching. Sometimes a kitten is sick and needs help, and that is a different situation. But a kitten being smaller than the others does not automatically mean it is failing.

That difference matters because it changes what you do next. If a kitten is not thriving, you need to act. If a kitten is small but warm, feeding, active and making progress, the answer is not always to do more. Sometimes the answer is to watch properly, feed well, and give that kitten time.

Why Some Kittens Are Smaller Than Their Littermates

Small kittens can be smaller for several reasons, and not all of those reasons are a problem. Sometimes the kitten is simply the smallest in the litter. Sometimes it is a girl beside a group of larger boys. In British Shorthairs, girls can be smaller than boys from very early on, so that can make the difference look bigger than it really is.

There is also the timing of conception to think about. Cats only take around 65 days to make kittens. If a queen is with a male for a few days, it is possible for kittens in the same litter to be conceived at different points during that time. A few days may not sound like much, but in a 65 day pregnancy, it can be a meaningful part of that kitten’s development.

That means one kitten may be born looking a little behind the others. It may be smaller, less developed, or even have less coat at birth. That does not automatically mean there is something wrong with the kitten. It may simply mean that kitten needs time to catch up.

This is why I don’t want new breeders to look at the smallest kitten and immediately panic. First, look at what the kitten is actually doing.

The Mistake New Breeders Often Make With Small Kittens

The mistake I see most often is trying to make the smallest kitten catch up by getting more and more food into it. I understand why people do it. When you are worried about a kitten, feeding feels like action. It feels like you are helping.

But a kitten can only eat what it can eat. You cannot force a small kitten to become the same size as its biggest sibling by putting more milk, more food, or more calories into it than its body can manage. Trying to push too much can create a new problem, and very often that problem is diarrhoea.

Diarrhoea in a tiny kitten is not something you want to create. It can set the kitten back, cause dehydration, and make everything harder. So if the kitten is otherwise doing well, I don’t look at it and think, how can I stuff more into it? I look at the kitten and ask whether it is feeding, warm, active, settled, and moving forward over time.

A small kitten does not need to be turned into the biggest kitten in the litter. It needs to be supported to grow well.

What I Watch For In The Smallest Kitten

When I have a small kitten in the litter, I don’t only compare it to its siblings. I watch the kitten as an individual. That is the part new breeders often miss because the size difference can pull all your attention.

I want to know whether the kitten is warm and settled. I want to know whether it is feeding well. I want to know whether it is active for its age and behaving the way I would expect. I want to see that it is gaining over time, even if it is not gaining as quickly as the biggest kitten in the litter.

When the litter starts solids, I want to know that the small kitten is actually eating. I don’t just put food down and assume. I watch. I present food if I need to. I make sure the kitten is consuming food and not being pushed aside by bigger siblings.

The things I’m looking for are simple and practical.

• Is the kitten warm?

• Is the kitten feeding?

• Is the kitten active for its age?

• Is the kitten behaving normally?

• Is the kitten gaining over time?

• Is the kitten eating when it starts solids?

• Is the kitten making progress, even if it is slower than the others?

Those questions tell me more than size alone. A small kitten that is doing all of those things is very different from a kitten that is cold, weak, not feeding, not gaining, or fading.

My Small British Shorthair Girl Who Caught Up

I had a British Shorthair girl who was tiny compared with her brothers. She had three big brothers, and they were big, strong kittens from the start. She was much smaller, and she also had less fur than they did, which made her look even further behind.

I remember the mating, and I suspect she may have been conceived a few days after the others. That would make sense with the way she looked when she was born. She was behind them in size, coat and overall development.

A newer breeder may have looked at her and thought, I need to do something to make her bigger. I need to work on her. I need to give her extra.  I didn’t do that. I watched her.

She was eating well. She was behaving the way I expected. She was active. She was doing what she needed to do. So I let her be, while still keeping an eye on her.

She caught up. She has now been desexed as a retired breeding cat, and she is fabulous. She was not a lesser kitten. She was a small kitten who needed time.

Good Food Matters More Than Extra Food

When a small kitten starts eating solids, food quality matters. If a kitten is only going to eat a certain amount, I want what it does eat to be good quality and appropriate for that stage.

I use and recommend Royal Canin Babycat for young kittens. I am also a Royal Canin ambassador, so I want to be clear about that. It is what I use in my own cattery, and I like it for this stage because I want kittens getting good nutrition from the food they are actually eating.

But good food and extra food are not the same thing. You can make sure the kitten has access to suitable food. You can watch that it is eating. You can make sure it is not being pushed out of the way. What you cannot do is make its body grow faster by overloading it.

The goal is to make sure the kitten is getting the right food in the right amount for that kitten. It is not to force the smallest kitten to match the biggest one by pushing more in than it can handle.

Sebastian Was Tiny Beside His Brother

Sebastian is the smallest kitten I can remember having. He was much smaller than his brother. His brother was a big, strong boy, and Sebastian was tiny beside him. He was weak at the beginning, and he needed careful watching.

But I didn’t overfeed him. I didn’t extra feed him for the sake of trying to make him catch up. I made sure he was okay.

When the time came for him to move onto solid food, I made sure he was definitely eating. I presented him with food and watched that he was consuming it. I made sure he was getting what he needed, and then I waited.

Sebastian is fine now. He is still smaller than his brother, and he probably always will be, but he is a great cat. I show him, and I am proud of him.

That is the point I want new breeders to understand. The goal is not to make every kitten the same size. The goal is to raise healthy kittens who are doing well.

When A Small Kitten Needs More Help

I want to be clear that I am not talking about sick kittens here. If a kitten is not feeding, not gaining, cold, weak, dehydrated, fading, crying constantly, isolated from the litter, or not behaving normally, that is different.

That kitten needs help. Depending on what is happening, that may mean helping it feed, giving extra support, getting veterinary advice, or acting quickly because tiny kittens can go downhill fast.

This is why breeders need to look properly rather than only reacting to size. A kitten that is small but feeding, warm, active and gaining is not the same as a kitten that is small and not thriving.

Those two kittens need different responses.

How I Support A Small Kitten That Is Doing Well

If the smallest kitten is doing well, my support is calm and practical. I keep an eye on the kitten, but I don’t turn it into a problem just because it is smaller than the others.

I make sure it has access to mum. I watch that it is feeding. I check that it is warm and settled. When the litter starts eating solids, I make sure the small kitten is actually eating and getting good quality kitten food.

I also give it time. That can be hard when you are new because waiting can feel like you are doing nothing. But careful watching is not doing nothing. It is part of breeding. Knowing when to help and when to let a kitten grow is part of the skill.

Some kittens catch up quickly. Some take longer. Some stay smaller than their biggest sibling but are still healthy, happy cats. That is okay.

My Advice For New Breeders

If you have one tiny kitten in the litter, don’t start by calling it a runt and don’t start by trying to push extra food into it. Start by looking at the kitten in front of you.

Ask whether it is warm, feeding, active and behaving normally. Look at whether it is gaining over time. Watch whether it is moving forward, even if it is not keeping pace with the biggest kitten. Make sure it has access to mum and good quality food when it is ready.

If the kitten is not thriving, act. If the kitten is small but doing well, support it without overdoing it.

Small kittens can make new breeders second guess everything. That is normal. But the answer is not always more food, more panic, and more interference. Sometimes the answer is good observation, good feeding, and time.

Small Doesn’t Automatically Mean Failing

Small kittens can catch up, and they often do it in their own time. Sometimes they catch right up to their siblings. Sometimes they stay smaller than a big brother or sister. What matters is whether they are healthy, active, feeding, growing, and doing well.

As breeders, we need to know the difference between a kitten that needs help and a kitten that needs time. We need to support properly without creating extra problems by overdoing it.

That confidence comes with experience, and it is exactly the sort of thing we talk about inside my New Cat Breeders Club. If you’re breeding cats or planning to, this is the practical side of kitten raising that helps you make better decisions when you are standing there looking at the smallest kitten in thebirthing box.