All adult couples can marry if they meet the legal requirements. To get married in England and Wales you must be over the age of 16. If you are under 18 you need your parents or guardians parental consent to get married. A person needs to be single, widowed or divorced to get divorced. One cannot marry their relatives, such as step-relatives or in-laws, unless under certain circumstances. Adopted children cannot marry their genetic relatives or adoptive parents, but they are allowed to marry the rest of their adoptive relatives. It does not matter if the partners did not acknowledge they are related. Such marriages are automatically void, e.g. invalid under the law.
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