Prandium Peculiaris

2. All of us.
4. The department of the Government of Ireland for whom you used to work for!
5. Suffering from decay.
7. Persons present at a particular event, function or meeting.
9. Twenty plus three.
12. One of Dublin's finest hotel establishments, its reputation surely 'bourn' from hard work.
15. A point, period, or step in a process or development.
16. Having requested the pleasure of one's company.
17. A most important person in an Irish family.
18. Supportive structure for an equestrian.
20. See title.

1. As the rhyme goes, the day on which if a child is born, they will work hard for a living.
3. Not feeling or showing gratitude.
6. The action or fact of leaving one's job and ceasing to work.
8. In the PM, second word of phrase.
10. Latin for: of or for the heart.
11. In the PM, first word of phrase.
12. Better, greater, or otherwise different from what is usual, just like you!
13. A sudden loud noise.
14. Ordinal number.
19. Meaningful pet name, sounds like ear.