It wasn't only Yemenite children but all Eidot HaMizrach communities this happned to.
My wife has an older brother who she never met as he was kidnapped shortly after he was born in the hospital.
They told my mother in law that her son died & many years later they heard we was in fact alive but have still not seen him.
He was kidnapped over 50 years ago
My wife's family are Persian & are here for 6 generations.