Oops! Got that wrong!

Have just had an email from a lady pointing out a glaring mistake in my tree.  Well, it is glaring now that I look into it closely.  Many years ago, before using the computer and internet for my search (i.e. I did it the old fashioned way - trawling through microfiche, hopefully making contact with fellow researchers through lists in magazines and journals etc.) I made contact with several people who were researching the family of James DANIELS and his wife Mary RILEY, from the Hunter Valley region of NSW.  This was my late first husband's family.  A son, Edward DANIELS, married a Sarah Sophia MOORE - and it is from this union that my husband was descended.  One of the DANIELS / MOORE children was a Sarah Ana Young DANIELS and each researcher had her married to a George MacLENNAN.  Over the years I added to this line with relevant registration numbers, spouses and children etc.  One correspondent very kindly sent me a scan of a photograph of Sarah Ana Young MacLENNAN, nee DANIELS.
Surprise! Surprise!  I got an email from a lady this week, querying my inclusion of the marriage of Sarah Ana Young DANIELS to George MacLENNAN.  She is a descendant of the DANIELS / MacLENNAN marriage.  She included a copy of the Marriage Certificate, which clearly shows that the mother of the bride, Sarah Ann DANIELS, was Ann COLLIER, and the father of the bride was James DANIELS.  A copy of Sarah MacLENNAN's death registration which I received years ago shows that her parents were - James DANIELS and Ann COLLIER.  At the time I remember thinking the Ann COLLIER must have been a mistake.  I never noticed that the father should have been Edward, not James.  Nor apparently had any other researcher. My biggest surprise though, was that the woman who pointed out the error was the same woman from whom I'd received information and the photograph many years ago.
It is now quite clear that Sarah Ana Young DANIELS should never have been linked with George MacLENNAN.  She seems to have disappeared off the map though, as no-one has been able to locate anything other than her birth registration.
One researcher has another theory - that Sarah Ana Young DANIELS is actually Elizabeth Young DANIELS.  The only reference I can find for Elizabeth Young DANIEL is a marriage to George MITCHELL in Narrabri in 1877.  There is also a Death Registration for an Elizabeth Young MITCHELL in 1936 - with parents James and Sophia.  If she is of the same family her parents should be Edward and Sarah.  I suppose it IS possible that the parents have been incorrectly reported and that the informant got Edward confused with his father James, and gave the mother's seond name rather than her first.  It is certainly strange that both DANIEL(S) girls have the middle name of Young - it would suggest a connection, but exactly what is unknown.