Brother and niece (mid 20's fashion designer) will visit Dublin in mid December - think it is arrive 14/15 and depart 19/20) They have accommodation set, but would like recommendations on places/things to do on this brief visit. First time to Ireland for both, believe they do not plan to have a rental car.
All suggestions appreciated

I suppose they chose just Ireland for certain reasons. As long as we don't know their interests, it's almost impossible to give good advice.

Long story, but Ireland chosen based on a great airfare to fill in for previous plans which fell through. She's a fashionista (in a good way) he's getting away for a few days with his daughter. Irish heritage. First time to Europe for him. Open to all suggestions

A fashionista might be interested in the Museum of Style Icons. It's a little bit out of the city, but easily accessibly by public transport. See https://newbridgesilverware.com/mosi

More generally: in mid-December, they should not plan for scenic tourism. Daylight hours are short, and the possibility of inclement weather (morning frost, rain during the day, limited visibility) is high. They should seek accommodation in the central part of the city. They might ramble a little, but should make a list of indoor venues that might interest them - perhaps the National Museum, the National Gallery, whatever their interests are.

There will be a lot of pre-Christmas buzz in the shopping areas. Pubs and restaurants might be busy with office Christmas parties (not all of them, of course, but they might find that one they hope to visit might be taken over for the night by a firm of accountants).

They are right about not hiring a car.

They can go to the top right of this page and click on Destinations. Then click Europe and Ireland and Dublin. When they do the research themselves they will be able to pose more productive questions here and have more confidence when they land.

Museums are some of the best in Dublin. lovendublin.com will let you know the local info. Shows, at the Gate or Olympia, concerts etc. Not a bad pub anywhere imo, do a literary pub tour. Trinity walking tour. Trip advisor is more friendly and helpful. Many Dublin locals there. I apologize for rudeness here.

Padraig is right about the Christmas parties. The Church is one they should check out and make dinner reservations. First night early bird is great at the farm, the larder the Winding Stair or Boxty house.

Thanks, Macross. Had a memorable meal at The Church right when it first opened.
No need to apologize for the prigs, they clearly have a lamentable tightly conscripted sphere of experience which manifests in their pissiness, so more to be pitied than anything.

So many people don't know about the Church, they never venture over the Liffey. I love the Smithfield area. Great pubs and music there. Your niece should check out some of the vintage clothing shops.

We are heading over for Christmas week. I’ve been researching like mad, but keep coming back with so many ideas. Then the whole iffy weather conditions, I posted a very open request as well. What to do with 4 days and nights after spending Christmas in Dublin?