How to find n'th previous Sunday with Java date time API or Joda-time?

How do we calculate previous Sunday or previous to previous Sunday or in general lets say how to find out sunday prior to n weeks? The catch is if today is Sunday then it should return today as Sunday and not last week.

Looking for Joda-Time or Java 8 time solution.

Edit: I tried

DateTime sunday = now
    .minusWeeks(1)
    .withDayOfWeek(DateTimeConstants.SUNDAY)
    .wi‌​thTimeAtStartOfDay()‌​;
DateTime previousWeekSunday = now
    .minusWeeks(2)
    .withDayOfWeek(DateTimeConstants.SATURDAY)
    .‌​withTime(23, 59, 59, 999); 

but if current is Sunday then this logic fails as it does not give today's date.