“Most importantly,” Plotina concluded, remembering her lecture, “you must not allow Dear Publius’s relationships with important people in the city to lapse simply because of a few hundred miles. Men are so forgetful when it comes to writing letters, so I shall rely on you for regular reports—”

“Really?” Sabina’s eyes snapped up. “So you won’t be coming to the provinces as well?”

“Naturally not. My husband relies on me here. Though of course there are visits.” Plotina cleared her throat pointedly. “For example, Vibia Sabina—if you should find yourself with child while in the provinces, then of course I would come to assist with the confinement.”

“Oh, look,” Sabina said. “Your barley water.”

“Don’t change the subject.” The Empress laid her shuttle aside altogether, fixing Sabina with a stern gaze. “I had hoped you would have provided Dear Publius with an heir by now, Vibia Sabina. A child of three or four could not accompany you to the provinces, of course—so unhealthful—but I would have been pleased to rear the child in your absence.”

“So kind.”

“To give birth in the provinces is not ideal. There are difficulties finding a decent physician, and as for a wet nurse—! But the problems are not insurmountable. Complete bed rest, retirement from public entertainments, a diet of barley and fish to avoid stimulation of the blood—”

“Calpurnia says it’s silly to shut yourself up like an invalid when pregnant. She goes rolling about the house like a great ball up till the minute the baby starts coming.”

“Your stepmother has very advanced ideas, but I cannot recommend them.”

“My stepmother has given birth to five healthy children.” Sabina blinked, innocent. “How many have you had?”

Plotina looked at her coldly. “Children are not granted to us all.”

“I have a feeling they won’t be granted to me either,” Sabina murmured. “Not unless Dear Publius’s tastes shift in fairly dramatic fashion.”

“Dear Publius will do his duty, and so will you,” Plotina snapped. “A man needs a son.”

“Trajan doesn’t.”

“I assure you, he has felt the lack keenly.”

Well. Perhaps that was not quite the truth. Years ago, Plotina had been certain that once Trajan became Emperor, he’d change his mind about the importance of begetting a son. She had been only thirty-one when he took the purple; it had not been too late. An Emperor needed heirs! But when she said as much, the words just rolled off him. “I’ll appoint an heir when the time comes. Best way to do it anyhow. Who knows what kind of son the Fates would send us? This way I can pick the best to follow me, not just pin all my hopes on blood ties.”

Plotina had let the subject drop from conversation but certainly not from mind. Trajan didn’t know everything, after all. Emperor of Rome or no.