looking for my grandfather

My grandfather was in Kenya in 1942 to 1950 (His name was Abdalla Fonseca) a Kenyan Bus Inspector in Nairobi.

My grandfather had 2 daughters and in a dispute for custody, he went to court to try and take his two daughers Amina and Rukiya.

I am the daughter of Amina and I need to find my grandfather or any members of his new family.

I have searched for 5 years now and I am getting nowhere fast - some Kenya Goans knew each other even after moving. Someone out can help me, please before its too late. I need to see my grandfather, please help me.