Oh that is messy
Just a few thoughts
First you should be aware that RootsIreland is known for transcription errors, the quote below will give you an idea of how some of the transcriptions were carried out. That may not be the case everywhere and to be fair the writing is very difficult at times but at least it's a warning to treat all transcriptions with caution.
Hi All
Just in response to the Transcriptions on Rootsireland, over twenty years ago
as a teenager i was pulled of the unemployment line and put on a six month
course transcribing parish records for Dublin North. There was no training and
the supervisor was only interested in finding out about her neighbours ancestors.
Out of twelve staff i was the only one who wanted to do it right, as i had experience
of trying to read the registers and with an interest in Genealogy. To finish always
check and check again ,what somebody else has discovered.
Thread that was taken from
http://www.rootschat.com/forum/index.php?topic=670189.0Second the parent's surnames seem to be unusual enough for there not to be two couples with the same names, which can happen.
Three, while you would expect a transcriber even a bad one to know what year they are working on it is possible that 1835 should read 1838, 5s and 8s are often difficult to tell apart.
but, Four, if that is the case and the 1834 and 1838 are brothers you would expect more children in between. Of course there could have been a string of miscarriages so it's by no means unheard of to have a gap, just worth keeping in mind.
I would go ahead and contact Waterford Heritage and ask if they can check, an error could have crept in when the transcription was being entered on the computer.
If you are lucky they may still have someone working on the registers for that church and the originals could hopefully be checked.
One more thing have you a marriage for this couple, are these baptism dates feasible?