The Ambarussa Brothers
Feanor's son who died at Losgar:
Mother-name is
Ambarussa -- which would yield
Amros in
Sindarin. Feanor asked
Nerdanel to give him a different name, so she said
Umbarto -- but Feanor changed this to
Ambarto (or "in some versions" he thought Nerdanel has said Ambarto) -- and had
Ambarto lived, this name would probably have been Sindarized as
Amrod -- but he did not live -- and so
Umbarto appeared to be the correct form, and thus if a name for him was encountered in Sindarin it was
Amarthan "Fated One".
The twins called each other
Ambarussa, but others called them
Minyarussa and
Atyarussa "First-russa" and "Second russa."
And I assume his Father-name was
Telufinwe "Last
Finwe" given the meaning.
And I cannot ask
Tolkien to give up this amazing naming scenario