Neef(s)

This word is the combination of the words niece & nephew.
Nee >ce .... niece
Nef > ew ... nephew
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Needs

"I took my neefs out to the movies today, all 6 of them"
Or
The neefs were bouncing off the walls after eating too much candy!

Neef(s)

There are 16 neefs in our family of 9 siblings.

My neef and I rode the train for the first time.
Meaning my one niece & one nephew took the train for the first time.