Alice de Burgh (N.N.) - Is there any evidence for the marriage to Sewallis?

Alice was most likely married to the Wallter de Burgh who is mentioned in the Pipe Roll for the 26 year of Henry II 1179--80 (for this see Ellis `Hubert de Burgh A Study in Constancy'), this shows that Walter had died by 1179-80. So Alice would only have been free to marry Sewallis de Shirley around 1180, however Sewallis appears to have been dead by then. Also the only piece of hard evidence that Alice ever existed is the grant Hubert de Burgh made `for the soul of Alice my mother', there's nothing that I'm aware of that indicates she was married twice.

Stephen