I was lucky just this summer.
I found my mother's first cousin's wife.
I found in the ITS records (the copy of Yad-va-Shem) a lady who had an
address in Budapest in 1946, according to the data I thought she was married
to my mother's first cousin.
According to Yad-Va-Shem my mother's cousin died (the testimony giver was
another cousin no longer alive).
She was 29 in 1946 so I hoped she remarried and was happy but still I wanted
to see if she (being much older then my mother) could remember things about
I did a complex search in Yad-Va-Shem and found some testimony pages given
in 1993 by a lady (not the one I was looking for) about 2 man: one her late
father and one her late husband.
This young man seemed to be the brother of the lady I was looking for.
I located the testimony page giver and through her, the lady in question!!!!
(With much help >from fellow genealogists to whom I can't thank enough).
I think we are in the last "window of time" in which we could still locate
the survivors alive (before they die of old age) and see if they can tell