If anyone is interested in unusual family relationships, this woman
Katherine Courtenay
is the only one I have ever seen who married her first husband's grandfather, which shows the lengths Tudor families would go to in order to keep property in the family. (At first I thought there must have been some mistake, but it's there in the pedigrees of all three families. It may even have been a genuinely voluntary arrangement rather than one where she came under heavy pressure: her second husband managed to outlive her by about ten years).
Mark