On marriage, the name of the wife is usually changed to that of her husband (though more and more women want to use their original family name in public), but, in this case, when the husband succeeds someone's family, he would succeed his wife's family. So, the person who "changed the family name" would be the husband. This sentence is from the wife's perspective.

Here is my guess.

When they married, the wife adopted her husband's family name. Then, some circumstances (such as death or disowning of a son, etc.) required for her husband to carry on the wife's family (although this very notion itself is no longer universally practiced). Through the system of 養子縁組 (adoption)、they both adopted her original family name. So, her name changed as well. There are other far-fetched possibilities, like her husband continuing some other family, but from the letter, it sounds like it was her original family.
I hope it helps a little.






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Note added at 2002-08-21 06:49:23 (GMT)
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A note: After WWII, there is no longer a legal provision for ¥"disownment¥" or ¥"disinheritance,¥" I don¥'t think. But it exists defacto in some cases.

Please be careful that under the new civil code the name of a spouse does not necessarily have to be changed at the time of marrige. This case seems to be the one that this particular spouse agreed to inherit property and perhaps business thereby changing his (family name) at that point in time.

Okay, everyone above explains different possible cases of this marriage with or with not a legal perspective. I'm just trying to pose another possible case.

Firsly, it may not matter so much if they have a son or not for their changing their family names. Apparently this couple is an eledery couple, who may not necessarily seek for their born-family names to use in pubilc situations in their 30 yrs post-marrige life. The point is that it's not clear who's in whose family officially when this marriage occurred. And who's going to change his/her name after all? They will have ever changed their family name only once in their life at this time? Or in the past? If the husband got into the wife's family after marrige and took its family name in an official manner, and for some reason, he has to succeed his wife's family, there might be a possibility for their families to change their family names. Sorry, I cannot explain from a legal point of view as I'm not aware in that field. But I'm just interested in posing this case can be somewhat more complex worth to be considered enough.

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Note added at 2002-08-21 16:36:48 (GMT)
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Sorry, I have noticed the comment below to know it\'s the wife who changed the name. All in all, there may be a possibility...

Another possibility,
He was an adopted husband,somehow in his own family,there's no more son or daughter to take over his family that he took over his family and went back to his family's name. That's why the wife's name changed.

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