johncro on Family Tree Circles

My name is John Parker Crosier,2nd. I know nothing of my genealogy and I would welcome assistance.
I only have a sister Jackie Crosier.

HERE IS WHAT I DO KNOW:
Father: John Parker Crosier. Never met,never saw, never spoken or written.Born 1919, where? Sister says last known place was in California.

Mother: Marion E Crosier.Born 1924, Jacksonville,Florida..maybe

My sister says there is a grandfather named William (Harry/Henry) Crosier.

This is the extent of my knowledge,I NEED HELP!