In Iceland the daughter surname becomes daughter of ”father’s name”. So if Orri had a sister it would be formexample Anna Oskarsdottir.Further off topic but as it looks like a boring end to a dull window here goes. This naming system won't fit in with the educational authorities in Vermont. In the interests of "equity" parents are now advised to stop using the terms son or daughter and stick to kid or child. So which sounds better Orri Oskarskid or Oscarschild!
Suppose the Vikings need to update now for it to work with gender neutrals :-)
Orri Oskarsþeir