Mary, Wife of James Landrum, Essex Co. Virginia

It's been awhile since I posted to this site, but thought I would put this out for discussion, since I haven't seen it brought up before.

Does anyone know who the real mother of Mary Brown, wife of James Landrum (Sr) was?It wasn't Elizabeth Allen as in Mary's will, probated 21 May 1754 in Essex County, Virginia, she says: "to son, Patrick, land given my husband, James Landrum, by my father,William Brown and mother-in-law, Elizabeth Brown ...."

Does anyone know if the children of William Brown,-- son William, and daughter Sarah,-- are Elizabeth's children or from William's previous marrige? And,too, who is Mary, the wife of William Brown in his will of 1705? She is referred to as Sarah'smother-in-law. If this is not Elizabeth(Elizabeth Mary Allen????), Elizabeth Allen would have died after August 1696 and William would have remarried.

Anyone have any thoughts on this group?

Thanks,
Linda J.