Age gap between siblings: What works best?

As your first baby starts to grow, your mind can often wander into thinking about having another baby. But what is the best age gap to aim for between siblings? 

Ultimately, you can’t plan that exactly (and sadly miscarriage and fertility issues can affect families birth spacing plans). Your thoughts may also depend on whether you have two the same sex or one of each as to how the family dynamic works.

We take a look at the practical pros and cons of different age gaps.

Less than a year age gap

Nine to 10 months age gap is obviously the smallest gap you can have, and can be quite tough but rewarding at the same time.

Pros

• The children are so close in age they will learn a lot about the world together.
• If they’re birthdays fall right, you could find they are in the same class which means they can share a lot together like twins.
• Being so close in age, they are more likely to enjoy the same toys and games. They may even find it easier to entertain themselves without you always having to be part of it, especially as they grow.

Cons

• This age gap would mean soon after your give birth, you fall pregnant again which means coping with pregnancy symptoms such as morning sickness and fatigue while looking after a newborn and getting through all the sleepless nights, pretty tough!
• When you are getting close to your due date, your eldest will only be around seven or eight months which is too young to understand what is going on and is often a clingy stage for many babies. Having to leave him to go into hospital to have your new one could be tough on him, and fill you with mummy guilt.
• Once your second baby has arrived, you suddenly have a newborn with all the regular demands to contend with but also another under one who still needs an awful lot of your attention and it could feel hard to split yourself in half to cater for both their needs all the time.

12 to 18 month age gap

Pros

• Children with this age gap still are very close in age so have all the benefits of enjoying a daily playmate as the eldest is still too young to have developed the feelings of sibling rivalry which means they are delighted to have a little play mate.
• Keeping the age gap small can also be a benefit for your time off work. It can make sense for one parent to stay home for a period of time to be with the young children, and ease back into work once both are that bit older rather than going back to work after one only to be there a short time before off again with number two.

Cons

• Having two this close in age has similar issues to less than a year gap. You have the pressure of two young ones needing so much of your time and it can take its toll on a mum trying to achieve this.
• If your youngest is only 18 months old when your new baby arrives, you are pretty likely to have two lots of nappies to deal with on a daily basis. Plus you may be breastfeeding your first when your second comes along and find you feel the need to wean your eldest off the breast before you’re both really ready.
• The younger sibling often grows up quicker when the older sibling is close in age so they may not be a ‘baby’ for long.

Two year age gap

Pros

• This is often a popular age gap as your body has had time to recover from the first birth and you are more than likely not breastfeeding anymore or changing nappies, yet not far enough beyond it that it feels too hard to start it all over again.
• This age gap can be good for your eldest too as he will be getting to a more independent stage and not needing quite as much of your time, and may even be starting playgroup a few hours a week.
• This is often quite a good age gap for practical reasons too such as passing down clothes and toys as well as having a ready-made nursery with cot and changing table all ready to be used again.

Cons

• It can be hard to explain to your toddler who is slap bang into the terrible twos that new addition is joining the family. Sibling rivalry will be at its height during their second year, so welcoming a sibling may not be entirely smooth running.

Three years and older

• Sibling rivalry may be minimised if you wait three years or more before having your second child. Your eldest has grown past the worst of this stage and will be old enough to understand what is going on, and can even be helpful when your new baby arrives.
• A bigger age gap means each child has more one on one time with mum. Your eldest has had at least three years of you all to himself and is off exploring new challenges of nursery and school allowing you a bit more time to bond with your new baby without feeling your eldest is suffering.

Cons

• The larger age gap can mean there is not so much interaction with the siblings as they are likely to be at very different stages meaning they don’t always want to play together. A less close bond between them could be the result in the early years particularly.
• It can be a shock to parents systems as they may be well passed the nappy stage, sleepless nights, and be tough to start all that again from scratch.

There’s no doubt that they are pros and cons to different age gaps so the moral of this story is there is no ‘perfect’ time to have baby number two.

Recent trends show that many families wait until the eldest starts school to have another baby, not necessarily a preferred choice of age gap but practicalities of paying two lots of childcare may be unrealistic for some.

Ultimately, whichever age group your children have, it won’t make any difference to a their relationship once they grow up, after all, have you ever heard anyone say their life was hugely affected by the birth of their sibling? Probably not.