I found this with Google. Either there were more than two children, or the obit writer got her parents wrong, or there were two men named William Huie who had children by Phyllis Pack.
Ms. Lisa Gail Blakemore
Ms. Lisa Gail Blakemore, 32, of Conway died Friday (Sept. 4, 1998) in Conway.
Born Oct. 26, 1965, in Morrilton, daughter of Bill Huie of Conway and the late Phyllis Pack Huie, she was a cafeteria worker at Kimberly-Clark Corp.
Other survivors are her stepmother, Marcella Huie of Conway; and two sisters, Cindy Huie of Conway and Rose Huie of California.
The body will be cremated. Arrangements are by Roller-McNutt Funeral Home.
It is from http://thecabin.net/stories/090898/obi_obits.html
a newspaper in Conway, Arkansas.
In my experience, obit writers don't distinguish between sisters and half sisters, so Cindy and Rose may be half-sisters. The fact their last names are Huie hints, but does not prove, that they are unmarried, which in turn hints, but does not prove, that they are relatively young, which in turn suggests they are half sisters, born after the divorce.