I like
Matilda a lot; as nns I like
Tillie and
Tilda but not
Mattie or
Matt.
Lily and
Eliana are names I've never enjoyed at all, so I don't think they would make a good sibset with
Matilda. Especially if
Matilda would be known as
Tillie -
Tillie and
Lily sound like Dr Seuss characters.