When you are planning international travel with children, there are a number of additional things you need to consider.
Does everyone in the family have their own passport? Even a young baby requires their own passport these days.
HOT TIP: Depending on your destination, some countries require your passport to be at least 6 months old. If you are purchasing a new passport for your overseas trip, consider making this your first chore.
Also check with the local embassy at your destination to determine if this is going to be an issue for you. There is no point planning the family holiday of a life time to be denied entry into the country of choice because your passport is new!
Also depending on the type of holiday you are planning, you may require a visa. This is something you will need to check based on your destination.
As a parent it is also recommended you carry a copy of your kid's birth certificates. Its one thing for them to have their own passport, but the authorities in some countries may want to see proof that you are in fact the parent or guardian of the said children.
Finally, copy everything! Photo copy all important documentation, from passports, to visa's, to itineraries. Keep a copy in your luggage as a back-up and a copy at home.
When you're planning international travel with children, register your family's details with a local embassy on arrival. Or better still check with your local government to identify your local representative. E.g. in Australia you can register your details with "Smart Traveller" which will ensure you can be contacted in case of an emergency.
Arrange to stay in touch with an extended family member or friend back home. If you have a schedule you are following leave a copy of this with the person back home.
In the event of a disaster or incident, always contact this person to confirm you and your family are ok.
If you have a mobile (as almost everyone does these days), set your phone up prior to your trip to allow international roaming. You don't have to have it on all the time, as you don't want to be answering unnecessary calls, however by checking it every night prior to going to be you can ensure any important news can still get to you.
All of these small things can help make your trip a smooth and enjoyable one.