If your friends comply with the marital laws of Kenya, their marriage
should be legally valid in the United States.
From the Bureau of Consular Affairs (part of the U.S. Department of State website):
"The validity of marriages abroad is not dependent upon the presence
of an American diplomatic or consular officer, but upon adherence to
the laws of the country where the marriage is performed...
In general, marriages which are legally performed and valid abroad are
also legally valid in the United States. Inquiries regarding the
validity of a marriage abroad should be directed to the attorney
general of the state in the United States where the parties to the
The embassy or tourist information bureau of the country in which the
marriage is to be performed is the best source of information about
marriage in that country. Some general information on marriage in a
limited number of countries can be obtained from Overseas Citizens
Services, Room 4811, Department of State, Washington, DC 20520. In
addition, American embassies and consulates abroad frequently have
information about marriage in the country in which they are located."
Bureau of Consular Affairs: MARRIAGE OF UNITED STATES CITIZENS ABROAD
Google Web Search: valid OR validity marriage OR marriages abroad
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