It seems this thread is attacking people for exercising their constitutional right against self-incrimination.
The 5th Amendment can be used in civil cases (including divorce).
According to Trump's former attorney, Michael Cohen, when they were investigating the family for business dealings Trump told him to make sure if they had to prison make it Donald Jr. rather than Ivanka.
It can be used in divorce IF what you are asked to testify about would incriminate you in a crime.