Interestingly enough, a "L.Mannex" disembarked at Wellington, New Zealand on a ship from San Franciso on 14th Feb 1920. On the 15th Oct 1920, a "Mannex" boarded a ship back to San Franciso, per New Zealand newspapers. In between that time my Mannex g.g.grandfather died in July 1920 in New Zealand after a long illness. Note: Mannex is used interchangeably with Mannix in New Zealand.
My gg.grandfather was also born County Clare, Ireland.
I'm interested in knowing if you have found anything out about these sisters (since your post 10yrs ago)