See this from Ovid Fasti (as inserted by Orberg into Cap XLI of LLPSI.
Silvia Vestalis caelestia semina partu
ediderat, patruo regna tenente suo.
Is iubet auferri pueros et in amne necari -
'quid facis? ex istis Romulus alter erit!'
Iussa recusantes peragunt lacrimosa ministri,
flent, tamen et geminos in loca sola ferunt.
I'm having trouble with the line:
'quid facis? ex istis Romulus alter erit!' Orberg's notes offer the following help: ['quid facis?' Amulio dicitur]
- so is he saying that this is a quote from Amulius (abl) or something that is said to Amulius (dat)
I have looked at two translations of this and neither has this in quotes and neither ascribes this line to Amulius. One seems to suggest it is the narrator speaking to Amulius.
The first translation has:
What was he doing? One of the two was Romulus.
-this translation is by A. S. Kline and doesn't dramatise the text.
- it seems to be a simple explanation.
Then we have
Rash man ! one of those babes will yet be Romulus.
- the second translation is by James George Fraser which does appear to do this.
So 'Quid facis' is a sort of dramatic interjections which in English could be like coming upon somone doing something terrible and crying out 'What are you doing?'.
I'm inclined to translate it as:
What is it that you do? one of these will be Romulus.
It's the narrator speaking and he's reminding the audience / reader that this is an important, yet terrible act.
I'd be grateful for any guidance.