He feels an open summons and lets it grab him -
"Oh, Miles has actually got lots better about melting at him, it used to be constant."
She pauses, then adds, "Neither has Gregor."
Please mean that, Aunt Cordelia.
"I would really like this situation to end with a minimum of heartbreak," she says. "But it's... tricky. I suppose it will all come to nothing if Cam vanishes never to be seen again."
"I mean, I suppose it would involve Miles disconsolately building Lego objects for a while, but I don't see a happy result elsewise either."
"The way I see it," says Cordelia, "I have two options. I can sit back and let them all work it out themselves, in which case they probably won't, because Miles seems to be having an uncharacteristic attack of shyness and I don't think Gregor is going to realize how he feels anytime soon... or I can meddle. I am a meddler at heart." She shakes her head. "I'm not going to decide anything until Miles tries the resummoning experiment, though."
He makes sure Miles has a copy of a nonbinding Cam summoning circle to copy out.
"Is there anything else that should be got out of the way before you dismiss me?"
"Nnno," he says, somewhat reluctantly. "No, I think we've hit all the highlights. And you have a nice long reading list of modern goodies in case the resummoning part doesn't work, right? Come to think of it, that's worth checking too - while you're there, see if you can conjure our books as easily as you conjure ones from your world. Who knows if it works the same way."
"I can conjure daeva summoning textbooks that were never published here while I'm here, I assume the reverse holds, but I'll go ahead and check if you want to leave me a minute in my house before you fetch me back again."
"All right. I'll dismiss you, and try summoning you again in a minute, and then try a few more times after that if the first one doesn't work, in case you just weren't answering for some reason. Any other tips for my resummoning protocol?"
"That's pretty much it. Do you want me to make most of the first circle for you, save you some time?"
Cam makes a dry-erase sheet on the floor, with most of a Cam-summoning circle on it, and hands Miles a marker with which to fill in the gap. "There you are."