I notice that Moya or Maire Brennan has two very good Irish Christmas albums. An Irish Christmas was first issued in 2005. The bonus version has 15 tracks. More recently (2023) she has produced Nollaig Gaeltach with another 13 tracks, most of which are not on the first album. One or two other stray Christmas tracks exist by Moya plus Christmas Angels by Clannad from 1997. A little too laid back sometimes, perhaps, but all good stuff.
