I accessed the following deed in the Registry of Deeds, Henrietta Street, Dublin. It gives a marriage date for Madeleine/Magdallen Crommelin and Francis Hutcheson of November 1728.
This deed mentions two members of the Lavalade family, the Rev. Charles Lavalade of the French Church in Lisburn, and one of his five sisters, Magdalen Lavalade who married Alexander Crommelin.
Also mentioned is James Crommelin but it's unclear where he fits into the Crommelin family.
http://alison-stewart.blogspot.ie/2012/02/notes-on-alexander-crommelin-and.html
22nd November 1737: Deed 88-230-623584
'A memorial of marriage articles bearing date the first of November 1728 made between Alexander Crommelin of Lisburn gent of the one part and the Rev. Francis Hutcheson of Ballymentisland (this was indecipherable) county Antrim, clerk of the other part.
By which said Articles after the severall (sic) sums therein mentioned should be paid by the said Alexander Crommelin, his execs or adms., into the hands of Charles Lavallade of Lisburn in the county of Antrim, clerk, and Robert Smith of the same town and county, gent......to be by them laid out for the Uses Intents and Purposes in the said Articles mentioned and the said Francis Hutcheson did covenant with the said Alexander Crommelin for the consideration therein mentioned and of the Portion to be paid by the said Alexander with Magdallen his daughter, now wife of the said Francis Hutcheson....
.....that if the said Magdallen Hutcheson alias Crommelin, should survive Francis Hutcheson, the said Magdallen should be entitled unto and should enjoy a moiety or half share of all such real or personal estate whereof the said Francis dye possessed of, the same be in lieu of jointure or dower which said Articles are witnessed by James Crommelin and Ralph Smith, Gent, and Thomas Walsh, Merchant, and David McClune, Yeoman, all of Lisburn....
...and this Memorial was signed and sealed by Magdallen Crommelin, widdow, and one of the execs of the said Alexander Crommelin and witnessed by the said Ralph Smith and Patrick Smith of Lisburn aforesaid Gent. Magdalen Crommelin (seal) - Signed - sealed in presence of Ralph Smith - Patrick Smith - the above named Ralph Smith maketh oath that he saw the articles whereof the above writing is a memorial duly executed by the parties hereto and also saw the above named Magdelan Crommelin, widdow. sign and seal the said Memorial and Deponent is a subscribing witness to this Article and Memorial - Ralph Smith - Lisburn.
(Dated here in Latin 22nd November 1737.)