I created a ‘Fact Type’ ‘Extra Marital Affair’ (Abbreviation ‘Affair’) using the ‘Family’ template. About 9 months before the birth of the ‘Ex Nuptial Child’ (rather than ‘bastard’ which has pejorative connotations blaming the child) I record an ‘Affair’ instead of a ‘Marriage’ and in the Child notes, note ‘ex-nuptial child’.