Identical twin sisters from Utah each recently gave birth to identical twins - again.
Kerri Bunker and Kelli Wall delivered twins within weeks of each other at a hospital in Orem, south of Salt Lake City. Years ago, they gave birth to their first sets of twins, now four- and five-year-olds, at the same hospital a few months apart.
Ms Bunker's newest twins arrived on February 13. Ms Wall's youngest twins were born about three weeks earlier.
Ryan White, spokesman for Timpanogos Regional Hospital, said some of the twins were conceived through in vitro fertilisation.
The 36-year-old women say they are not just sisters but best friends, neighbours and co-workers. They say all nine children will grow up together. Ms Bunker also has a two-year-old child.