Is it genetically possible for your grandmother to be your sister?

[tralalalaserqueen]

Okay, I know this is extremely strange, but it's just a thing between my friends and Facebook siblings. I would appreciate getting some help trying to figure it out though, if anybody knows? Thanks!

[Becky N]

no because you mother would have to give birth to both you and your grandmother (her mother.) I suppose it would be possible if you time travelled, but seeing as that is unlikely.... i would go with no.

[joemoser1948]

It's not NORMALLY (i.e., socially) possible, genetically, but strange marriage relationships could give rise to such an arrangement. I guess it would be PHYSICALLY possible for your father to have sexual relations with his mother or his mother-in-law and a resultant live-birth - as morally reprehensible as that is - would result in the genertic relationship

[n0way07]

i am 99.9% sure its impossible for that to happen even if she were to adopt u

[Libby]

Nope, not possible from a genetic standpoint.

[Lady Alyk]

Not really, not genetically.

Though, through some strange marriages, it might be possible. That would probably take a very young, and strangely married family.

[Jelly anne]

Yes! Mummy has a girl, grandma, who then has a boy, who is daddy. Then mummy and daddy have a kid which is you. Very odd incest, and lots of 12 year olds with kids so the age thing doesn't rule it out, but technically, it could happen...

[AL]

if your great grandfather slept with you r mother and produced you then your grandmother would be your sister or more exact your 1/2 sister