Hi Jenn,
Ann's brother, Donald MacLennan, emigrated to NSW (arrived in 1839).
Ann's nephew, Roderick MacLennan, emigrated to SA in 1867 (I've found his family in Australia thanks to rootschatter's help).
I only have the marriage register for Alexander McGregor, which states he was from Torridon, Applecross (no parents name) and his mention in the 1841 census in Applecross.
Thanks for your help,
Francisco