Gaybbagrandson on Family Tree Circles

My name is Daniel Brown,
My mothers maiden name is Kathleen Swan Gaybba,born in Montreal, Quebec Canada,daughter of William Gaybba.
William married Helen Downs Weir Boyle in 1925 in Montreal.
They had 5 children, Dianna, Anna (deceased), Richard(deceased drowned at a young age), Kathleen(my mom),
and Helen.
William Gaybba was my grandfather and I am 1 of Kathleen's 10 children.
My grandfather William met my grandmother on a ship coming to Canada.
My grandfather was always elusive about his past according to my mother. As a kid growing up in Canada I was always intrigued by my mothers maiden name.

My cousin Susan Pate has done some research as have my sisters Deborah and Shairn.

I believe my grandfathers father was William Eugene Gaybba, married to Marie Lawson of South Africa.
Could it be possible that William Eugene Gaybba, is the son of James, Matthew John, or William of Scotland
who arrived in South Africa in 1849 or 1850?
From what little information we can pry from our 82 year old mother apparently my grandfather was somewhat of a badboy.
I have looked on line and I believe that estelleg, mimsi,and brian, and I may be of the same Gaybba line but I have only started my research.
My grandfather had a sister who he loved her name was Dianne.
My aunts always tell me I look like a Gaybba......Oh course I take this as a compliment.
If you can provide further information on my ancestry I would be most grateful
Thank-you to Estelle, Mimsi and Brian for their valuable information.

Daniel