If it is the same boomers then Patrick's parents were Francis Hughes and Susanne Milligan. Don't know a lot about the Hughes (still filling in!) but they had at least one daughter Alice who married somebody (unsure of first name)Stafford I think and I've been in touch with another grand-daughter (or even great-g-d!) Sineann Matthews - ring any bells?
Where are you based? UK? Quickest way to get info (and save a lot of typing!) is to sigg up with Genes Reunited (www.genesreunited.co.uk) and search for Brigid Boomer and you should find me (John Braniff). Contact me via them and I'll give you access to my tree and you can see what info I have and I'll try and fill in any gaps after that.
As I said, I've not managed to trace them before they were in Portaferry - more digging to do. The Boomers were originally Hugenots (Protestant) but those in Portaferry were Catholic so I'm not sure where/when they changed. I know Liza Sullivan had a brother Patrick as my mother remembers tales of him coming to visit and asking for a ferry across Strangford lough in Irish (she thinks they were from Meath (or that area). There was also an Annie who sponsored one of the Boomers at baptism but not sure if she was Pat's wife or a sister. James' brother Phil has his father listed as Rainey Boomer, blacksmith - I'm guessing that's from Rene?