Actress Sian Barbara Allen, a staple of 1970s television, has died at the age of 78.

The actress, who starred in popular shows such as The Waltons, died of Alzheimer’s disease on Monday in Chapel Hill, NC, according to an online obituary.

Her sister confirmed her death via a post on Facebook, writing, ‘My wonderful sister, actress Sian Barbara Allen died peacefully today after a long illness. This loss is too hard.’

Allen, was born in Reading, PA on July 12, 1946,  studied her craft at the Pasadena Playhouse beginning in 1964.

The versatile actress  was a well-known face on television beginning in 1971 with her appearance on Alias Smith and Jones.

She later had appearances on Gunsmoke, The F.B.I. and the popular Love, American Style.