In 2022, Fr Mullan was involved in helping to commemorate the centenary of Feis Dhoire Cholmcille and in a video interview about his thoughts on the feis he said: “The feis became, really, my whole life when I was here in Derry city. When Bishop Daly asked me to take it on, it was in a lull because of the Troubles and he wanted to revive it. He had just been made bishop, so ‘muggins’ was asked because I did Irish dancing. I never, never regretted giving my time to it. It made what I am – a physical wreck – but very happy.”