 Furthermore, Anne's son Richard also became heir general to the earldom of March, after her only brother, Edmund, 5th Earl, died without issue in 1425.Their father Roger Mortimer, 4th Earl of March had been named heir presumptive of Richard II before Henry IV's accession; although it had been passed over at the time, Anne's son Richard also inherited this claim to the throne.Richard was executed following his involvement in the Southampton Plot to depose Henry V of England in favour of the Earl of March.