A nakomeling (literally: one who comes after) is a descendant. It’s a term you may encounter in wills or endowments, for example when certain branches of the family get an inheritance or rights to a recurring payment or other provision.

Pierre de Moucheron (1508-67), his wife Isabeau de Gerbier, their eighteen children, a son-in-law, and first grandchild. Credits: Unknown painter, collection Rijksmuseum (public domain)
Dear Yvette,
Thank you for sharing your great talent, and education. My grand mother was born in Amsterdam, her name was Elizabeth Albert Van Der Weijden.
My very best to you,
Keith Arnold