There's just a possibility that Richard McGreevy's father was also called Richard McGreevy, see what you think from the following. To recap, the Richard who married Sarah McGraw / McGrath in 1845 and had surviving offspring John, James, and Sarah Ellen, was born c. 1817 and would have therefore been around mid 20s when the following story was reported by the Northern Whig (Belfast) on 15 November 1842.
LOSS OF LIFE. - A PILOT AND THREE BOYS DROWNED. - On Wednesday afternoon, the 2d instant, Richard McGreevy, a branch pilot belonging to this port, left the quay, to meet the steamer Aurora, which had left Glasgow, that morning. His son, who is a supernumery pilot saw him about five o'clock, in the afternoon of the day in question, at which time they parted company - the son, with the intention of picking up some small craft, and the father, of proceeding, as it is reported, in quest of the steamer, which arrived in port, that night, without having McGreevy on board. His friends, not hearing of him or his comrades, began to entertain serious apprehensions of their safety ; and, on Friday morning, the yawl was discovered, bottom up, on the shore, near Islandmagee. All hopes of McGreevy and his companions having been saved, are now abandoned ; and various conjectures are entertained, respecting the cause of the accident. The general opinion is, that the yawl had been capsized, in a squall. Others suspected that the steamer might have come into collision with her. From the latter supposition, the friends of the unfortunate men were anxious to have an investigation ; and, accordingly, an examination of the Captain and crew of the Aurora took place, yesterday, in the Police-office, before Thomas Verner and R.D. Coulson, Esqrs., the result of which was, that, from the evidence produced, there were not the smallest grounds for attaching blame to either the Captain or crew of the Aurora ; nor was there the slightest reason to suppose that the yawl had been run down or struck by her. The boat is at present in Belfast, and has been examined by a great many persons ; and it is the universal belief, that the injury she has sustained was occasioned by her striking against the rocks, or on the beach, after she had been capsized, As respects McGreevy himself, we must say, that there was no better conducted pilot connected with this port. We lament to say, that he has left behind him a wife and a large family, who, we are informed, will be wholly dependent on the exertions of the son, to whom we have already referred, and who is a very well conducted young man. We trust that the Ballast Corporation will appoint him a branch pilot in the room of his unfortunate and lamented parent.
Rather frustrating that the son's name isn't mentioned...
