Dina Diggle was a Hobbit of the Diggle family, its only member known by name.
1 She married
Gundahar Bolger and together they had two children,
Adalgar and
Adaldrida. Since Gundahar was born in T.A. 2774 it is likely that Dina was born around that time as well. Her date of death is unknown.
References
1 - J.R.R. Tolkien, The Lord of the Rings, Appendix C, Bolger of Budgeford