- her husband just died?
- there was a change in the law?
- her financial status changed?
All of these events could have created records, especially the first one. In the second case, reading the act under which she applied may give details about her husband's military service, length of their marriage, etc. And in third situation may be referenced in the widow's testimony.
At any rate, try and determine why the widow applied when she did. There may be a genealogical story behind that reason.