I wouldn't even entertain the idea. My daughter will be locked up until she is 65, then nobody will want her.
Cousins
Your daughter's daughter is your granddaughter, and you would be her grandmother or grandfather.
She is your first cousin.
2nd cousin
Your daughter is your brother's niece. Your brother is your daughter's uncle
Your nephew and your daughter are first cousins.
Incest
yes it is ok!....in fact you and that person can get married if the relationship is at that level all you need is parental approval
my great grand-daughter
she would be my cousin
You are First Cousins
You are cousins