As others have given known examples, I'll toss one in.
My gt-gt-grandmother's husband died in 1878, leaving her with five children; she then had two further children, 1880 and 1882.
When the one born in 1882 got married, she put her mother's dead husband's name as her father and his profession, even though he'd been dead 4 years when she was born.
As has been said - depending on what you were told, what you know, what you think, who is asking, how they are asking, who can hear your answer, how "fearful" you are etc etc .... the name can be anything at all, for any reason.
Maybe the 1882 girl never knew/did the maths to realise, or maybe she was embarrassed as she was marrying "a bit of a steady catch".
We don't know what people were told when they were growing up.... or what they invented for themselves.