"You do that, Junior Miss," Tony told Lunella, before he walked away. "I'll be fascinated to see what you come up with."
On hearing Peter's question, he glanced over at Cap and Bruce with raised eyebrows, because he was very glad for once to hear an accusation that was directed at somebody other than him. Having been on Titan, then stranded in space, then imprisoned by Ultron, Tony couldn't be blamed for the current disposition of Vision's body.
"Nobody knew what to do with him," Bruce said. "This was right after the Snap, you know. We didn't have Vision's last will and testament handy. The Wakandans put him here, thinking maybe somebody could revive him.
"Then after we found out about the directive, we still didn't know what do to. He's got no next of kin to consult. You can't cremate vibranium. If we buried him, somebody might dig him up and use him as a weapon. We talked about a memorial service, but we were still hoping to bring back the Snapped first... like Wanda, she'd want to be there." He looked down sadly upon the lifeless gray face. "This seemed like the safest place in the meantime."
"Put him away," Tony said, his eyes stinging. "Let's set up, and then get that Cradle."
For the next half-hour, he and Bruce and JARVIS busied themselves with 3-D schemata and virtual modeling, working out the details and ensuring an adequate power supply. Peter's assistance was welcomed, and Tony occasionally accosted Lunella to see how she was up to and if she needed anything. It occurred to to him to wonder if his own offspring would be anything like her, which made him more interested in what she was doing.
Steve, meanwhile, went to tell Okoye, Natasha, Nebula, Rocket, Carol and Rhodey what was going on and to make sure the Wakandans approved of the plan -- since it required their cooperation and their vibranium.