The two do not see each other again for 17 years.

She did not see them again for more than 20 years.

At least, something which has not been seen for more than 20 years.

When we have not seen each other for so many years?

They are all he has seen of them for seven years.

The four had not seen each other for more than two years.

In fact she would not see her again for many years.

But things happened, and I didn't get to see her for six years.

His parents would not see him again for seven years.

He had not seen her for more than five years.