Although the Smederevo Fortress was the work of Đurađ Branković (completed in 1430), Irene apparently had a role in its construction; one of its towers is known as "Jerina [Irene]'s Tower" (Serbian: Јеринина кула / Jerinina kula), and she is blamed for causing hardship on the inhabitants of the countryside by levying taxes and recruiting forced labor for building the fortress.

According to the account of historian Michael Critobulus, upon the death of Đurađ Branković, his youngest son Lazar became Despot under her regency.

However Lazar swiftly deprived her of all authority and treated her so badly that she tried to escape to the court of Sultan Mehmet II with her daughter Mara and her son Grgur (Gregory).

[3] No contemporary source states which of Branković's five children were also Irene's, although the youngest, Catherine, bore the name of Kantakouzenos, and Mara was "clearly" the daughter of Eirene.

[9] Irene, being a Greek, and with her brothers also being very influential to the new despot, people began to dislike her, attributing to her many vicious and evil characteristics including that building of Smederevo was her caprice.

In local tradition she is described as a cruel queen who threw children from highest tower to dark river Đetinja.