Welcome to Healthcare Magic forum.
Hernia is protrusion of any normal part of our body through a abnormal opening. In your mother there might be protrusion of intestines through an abnormal opening from the Umbilicus
. A doctor need not ask for an investigation to confirm that it is umbilical hernia
as it can be diagnosed through a clinical examination.
But investigations like Abdominal Sonography
might be required before Surgery. Surgery is considered to be the only definitive treatment.
Please trust your doctor on this and follow his advise.
Hope this answers your query.
Wish your mother a speedy recovery.