Three Allies of the United States today are Britain, France, and Japan, for example. All three have been close allies since world war two and have been important partners in the international community when it comes to making making policies or implementing programs or anything similar that might be necessary.
The United States would mostly support them in times of war through their military. The United States has one of the largest militaries in the world and also one of the most developed and they could provide not only material support like soldiers or machinery, but also things like logistics or things necessary for espionage.
In times of peace, the United States could help them by supporting their plans and programs in organizations such as the European Union and United Nations which would provide legitimacy to their actions. They could also help with things like relief in case of a natural disaster, for example if a Tsunami or a Typhoon hit Japan.
In times of peace they could support the United States also in their dealing with worldwide politics and United Nations programs. The United States are an important player in the United Nations and France and Britain could support it in new policy making which could enable them to get majority votes and pass new ideas.
The French Revolution was an especially violent conflict that ended (at least temporarily) the monarchy in France. This brought in instead councils that made decisions.
The child will automatically gain citizenship if he is under the age of 18.
Since 18 is the age that you become a legal adult, if the child is under the age of 18, he will gain citizenship because he is still legally under control by his parents.
