Good idea Donna - here is my ongoing brickwall:

Elizabeth OATES b circ 1826 Douglas, d/o Robert and Mary Thompson. Apparently married (perhaps) to a David RICHARDSON b circ 1818 in Cumberland, England. This couple emigrated to the USA in 1848 through New Orleans, Louisanna. When I say married (perhaps), I mean that this might have been only a liason as no marriage particulars can be found. David had 4 (wives); the other 3 have been documented. I am the 2nd grt granddaughter of Eliza/Elizabeth and David. Eliza and David separated in the mid 1850s with Eliza returning to the IOM with 2 of her youngest children (and perhaps her only biological children), where she died in 1876 in Douglas. I would be very grateful for any suggestions as to where to look next. I have researched the usual sources (census, BMDs, passenger lists, emigration, wills, etc.), but hoping I've missed something new to try.