I am trying to discover the roots of my family name

Hi, my family name of Giblin has always intrigued me. The name is not common. I was born in Beckenham Kent where the family can be traced back a couple of centuries, I am told, but I have no real history. I lady called "Granny" Giblin ran a bakers shop in the High Street in Victorian times and my grand father John  Ernest Giblin and his cousin Samuel Giblin were born in the town in about 1885.

I have just had a DNA ethnicity test which shows I am 44% Irish 22% Scandinavian and 20% Saxon/Norman. But only 2% British! So the Irish connection is really strong.

My wife is a Scot and I enjoy wearing the Scotttish kilt on Burns Night - can't now of course! But I can wear an Irish kilt. I believe the County of Roscommon and the County of Cork have been areas where the family have come from but really do not know.

Can anyone give me the History of the name attached to Ballygiblin. A house which I have just discovered is up for sale. 

Many thanks

Peter John  Giblin   aged 64.