The definition of a child varies, but normally it is based on age. There may also be minimum weight and height restriction on some attractions for safety purposes.
Articles on travel with children to specific destinations:
'''Children under 2''' have the option of travelling as a '''lap infant''' and will not be assigned a seat. Lap infants often travel free on domestic flights, and at a 10% fare on international flights, plus any additional surcharges. During take-off and landings, '''infants should be held''' in an upright 'burping' position, with their head on your shoulder and your hands supporting their back and neck. Some infants are more comfortable '''nursing''' during these periods and most flight attendants will allow it. Saving a feed for the descent can make the baby much more comfortable. With some carriers a '''lap belt''' is available that loops into the adult belt and then around the lap infant for take-off and landings.
Some airlines do not permit infants to be booked through their website, and you must contact the call centre or a travel agent.
Infants younger than one week may require a document from a doctor.
If you would rather have a seat for your baby, some airlines have an infant rate, but this can be as much as 90% of the regular price. On airlines based in the USA, '''Seated infants''' must be in an FAA approved car seat appropriate for their age and weight. They must be buckled into their car seat for take-offs and landings.
On long haul flights, consider a '''bulkhead seat''' Arm rests don't go up (the tray is in the armrest), and you have to stow your carry-on bags in the overhead compartment during take-off and landing since there is no seat in front of you. On the plus side, bulkhead seats have more legroom, often enough for moving around without disturbing the occupant of the aisle seat, and there is no seat in front for the child to kick. Some airlines will let you book these when you purchase tickets, others give them out at a first-come-first-served basis at check-in only. If you have infants under 6 months old on a long-haul flights (over 5 hours) you can request a '''sky cot''' bassinet which attaches to the bulkhead.
'''Children over 2''' must have their own ticket. Children between 2 and 12 are usually given a 75% discount on full service international airlines, but usually have no discount on discount international or domestic airlines. Discounted children's tickets may have different baggage allowances so check before showing up. Children's meals are available on some flights offering meals. The usual rules for special meals apply, and they must be ordered in advance. Picky eaters may prefer a bag lunch.
'''Unaccompanied children''' are usually children under 12 travelling without a supervising adult. Not all airlines accept unaccompanied children, especially discount airlines. An unaccompanied child may be required to travel on a full adult fare, and additional fees may be charged. Unaccompanied children will need to be collected at their destination by a named caregiver and may be returned to their point of departure if not collected. Some airlines do not permit connections and no airlines permit connections to different airlines.
Airports often have play areas as well as nursery or parent rooms with changing tables and rocking chairs for nursing.
Parents with smaller children can keep their hands free with a '''baby sling''' or '''baby backpack'''. Slings can be used on the plane with small infants and can give some privacy when nursing. Many parents find a '''stroller''' a life saver when flying. Some airports and airlines will let you keep a stroller with you until boarding, and the stroller is brought to the gate at arrival. Some airlines allow one stroller to be check at the gate in addition to normal baggage allowances.
Young infants are often content to nurse and sleep through a flight, while older babies will require some '''entertainment'''. Bring small bags of snacks and toys and dole them out every 10-15 minutes so there's always something new to play with. Small amounts of playdough, books, and crayons are good ideas. Avoid anything messy or with small parts that can get lost under foot. Anything too noisy will probably not be appreciated by other travellers. Take '''walks''' up and down the aisle every half hour or so and look for other babies and young children. Making a friend (and commiserating with other parents) can make the flight go faster.
Flying in a group can be fun as children can keep each other busy. On a large plane such as a Boeing 747, you will want to reserve the four seats in the middle. The armrests move up allowing for children to sleep. On smaller planes pair one parent or old child with younger children and make sure everyone is supervised at all times.
If trans-continental flights seem too long for children, try planning a stopover or two in between. For example, Air Canada has a five-hour flight from St. John's, Newfoundland to London Heathrow for a trans-Atlantic trip. Trans-Pacific flights are a bit more challenging, but Hawaii and Guam stopovers are possibilities. Keep in mind that this involves more take-offs and landings, as well as getting from one flight to another, so it's a trade off.
Many cities in the United States require the use of a child car seat in a taxi but some (New York City is a prominent one) exempt taxis from these requirements. In London, black cabs are exempt from the carseat regulation but minicabs must provide one on request. If you want your child to be in a suitable restraint, either carry your own or check local regulations before traveling.
Car seat regulations are lax in many developing countries and you may choose to carry your own. However, in many countries, especially in South Asia, taxis may not even be equipped with seat belts. In these countries, you will either have to learn to live without a car seat and safety belt, or carry your own car seat and hire a car equipped with working seat belts.
Several companies make small, portable, restraints that act as travel-carseats. These can be folded up and packed in a day bag for use in rental cars and taxis. These only work, however, if there are adult lap or shoulder belts. In more developed countries a child car seat imported may not have the connections or be certified for use in the destination country, and again you may need to request one when you hire a taxi.
Sharing a seatbelt with a child can be dangerous.
Many countries will require that all adults who have a legal parental relationship with a child agree to a passport being issued to the child. Allow extra time for the application if you think you will have any difficulty demonstrating this.
Single parents travelling alone with their children can often be asked questions at immigration about the status of the other parent. Usually a strightforward reply will suffice to satisfy the immigration official. A single parent with a different surname to the child may have additional questions to satisfy immigration. Some countries recommend a letter from any legal guardian who is not travelling with you, agreeing to your travel plans, or documentation of court orders granting you sole custody or similar arrangements. Some countries can have an official requirement for a particular type of documentation. Check with the appropriate department of your desination to make sure.
Friends or relatives travelling with children should seek advice from the authorities at the origin and destination as to what, if any, documentation they may require.
In general, if court orders apply to the care of children, for example following a divorce, you may wish to seek legal advice both as to whether there is any risk of them being challenged at your destination. Take particular care if your child or your child's parents are citizens or possible dual-nationals of the destination country.
'''Bottlefeeding''' Preparing milk or formula for young children while travelling requires some planning. On an extended trip or road trip it may be worth bringing a small electric kettle for boiling water unless you know you will have a facilities available. Bring a bottle brush and soap for cleaning bottles or pumps in bathroom sinks. Check the availability of formula at your destination, or bring your own. Travel may not be the best time to try changing formula. If your child has special needs (such as soy based or organic/wheat-free formula), check that these are available at the destination. Mothers who are expressing and storing breastmilk for bottlefeeding will need to check on appropriate refrigeration facilities.
Hotels often offer in-house babysitting services or can refer you to a local service.
Travellers, especially those on long trips for business or study, may have children born while outside their home country. Aside from making sure that local birthing or medical facilities meet your requirements, you will wish to make sure that your child's birth is sufficiently well-documented that you can at some point take them home! Check with your home country's embassy about how to register the child's birth and apply for or record their citizenship. Children born in some countries become citizens of that country by right of birth, but this is not necessarily the case: if not, you will not only have to establish their citizenship of your home country but also meet any visa requirements and so on for them to stay with you.
At least consider the issue of children getting lost. Your children should have age appropriate knowledge of what to do when lost: generally stay where they are, and wait for you to find them. If speaking, they should be taught their name, and ideally where they are staying.
Consider carefully what to teach your children about '''strangers''': it's true that some strangers pose a threat to them, but many more will be able to help them if lost or in trouble. Children who are taught to "avoid talking to any stranger" have been known to hide from rescuers or would-be helpers when lost.
Children may have special health needs while travelling: