Just wondered if anyone knows this? To cut a long story short, my dad's mum was pg with dad when the father (grandad) got killed on a motorbike. She used her own name for dad and it was just kept hush hush about dad's dad. We've never known his name and it's always niggled me. I wondered if she put his name on the birth certificate and my mum says she's never seen one but wouldn't he have needed it to get married? Dad's mum isn't alive now but her 94 year old husband is (step grandad) but I don't want to ask him as it's stirring up old memories.