Irwin can be found hanging out in a broken down building near Bob's iguana stand. He had to flee from his home, which lies on the outskirts of the Hub, when raiders appeared from nowhere and invaded it. They now use it as a base for their operations.
He used to have a pet donkey named Pugsley, but it died in the raider attack.
Help Irwin: He wants the Vault Dweller to rid his farm of raiders. He claims he would go back, but the raiders threatened to kill him if he did so. If the Vault Dweller agrees to kill the raiders, he will be escorted to his farm. After the farm is cleaned out, and the Vault Dweller lets Irwin know it is safe to return, he gives a .223 pistol as a reward.