Possibility

Shock was registered on Itsumi and Itachi's faces. 

"What? What is the matter? Why the shocked expressions on your faces?" Sakiko asked. 

They both exchanged a look at each other before looking back at her. 

"Umm Sakiko, you may not have realized it or I don't know if mum told you, but he has the same name as your twin brother. Except for the Uchida of course."

"You're kidding right?" She looked at their faces, "Oh no, you're dead pan serious" she now had the shocked expression on her face. 

"It's the truth Sakiko" Itachi confirmed her thoughts. 

"No wonder you guys feel happy around each other. You must find out okay."

"All right I'll try. I do not know if he really is... "

"No negative thoughts here, Sakiko."

"Besides, we never found his body. For all we know he might be our lost brot