A passport, immunizations - check with your travel agent they will have a list of what you need to do to prepare.
You need a passport to travel there from the US.
I have vacationed in the Dominican Republic, and the only document I had to have was my passport.
No if she has a passport she could travel anywhere without a USA passport
Yes.
The Dominican Republic is an independent nation.
It is generally a good idea to have a passport when traveling. US citizens may enter the Dominican Republic without passports using other forms of ID and this is also true for children.
There is no US state that is the same size as the Dominican Republic. The closest states are Maryland (about half the size of the Dominican Republic), and West Virginia (about 1½ times the size of the Dominican Republic).
Anibal De Jesus De Castro Rodriguez is the Ambassador to the US for the Dominican Republic.
They can go to Hawaii but not to dominican republic because its not a part of US.
Yes if you do not have any valid US Visa. No if you have a valid US Visa.
In order to travel to or visit the Dominican Republic, the first essential document a traveller requires is a valid passport from their home country. Other documents are secondary to the passport.
Your question is a bit misleading, but yes you could travel from the US to the Dominican Republic with a Mexican passport. In fact many people need to make such kind of connections as Mexico doesn't have direct flights with many countries; one instance would be Portugal: Mexican tourists have to fly to the US, Spain or the Netherlands to reach Portugal.