A 1993 clip has emerged showing a concerned mother calling into CNN's Larry King about her daughter's problems with a 'prominent senator'

Former Joe Biden staffer Tara Reade confirmed it is her mother's voice 

Reade filed an official criminal complaint against Biden on April 9

She claims he sexually assaulted her in her 20s when she was on his staff 

Her superiors in Biden's office did nothing about her complaints, she says

Biden has vehemently denied the accusations and that a complaint was made

The clip appears to confirm Reade spoke about the alleged assault at the time