What Relation Are My Nieces Children To Me ?

[Gromit]

My sister's child is obviously my niece and I am her uncle.

My niece now has children of her own, a boy and a girl, how am I related to them ?

Am I their great uncle and are they my grand newphew and grand niece ? Or something else.

Thanks in anticipation 👍

[brainiac]

Yes, you're their great uncle

[ToraToraTora]

Grand or great Nephew/nice are both correct. You are their great uncle.

[sandyRoe]

What relation would a grandchild of my niece be to me?

Please excuse the intrusion, Gromit

[Cloverjo]

I think you are their great uncle.

[Cloverjo]

sandyRoe, I think you would a great grand uncle

[Cloverjo]

^be^

[ToraToraTora]

12:13 Great Great niece/nephew

[Gromit]

Thank you all. 
I had a celebration for my 60th birthday and I met my great niece and nephew for the first time. I didn't know what to call them in an email to a friend. Now I know, cheers 😀