This reflects not only the changing times, but also the legal complications that may arise from such a situation. Under the existing laws of the land, a spouse in the UK is allowed to file for a divorce on grounds of infidelity. This has to be proved conclusively, of course, and the respondent, if he or she wishes so, has the right to defend the case at court. The third party involved may be called for testimony. The legal matters will include decisions concerning child custody and inheritance, including any child born out of wedlock.