Perhaps it did not. They chose to become immortal, and no longer had a reason for ... children to exist. It may not have occurred to them to preserve anything related to them. Perhaps to... downsize or to make it easier to live with themselves by purging reminders after they had changed and were... trapped with their decision.

[Given how even clothes were difficult to procure here, the state of the food replicators, and even finding items like incense.]