As of right now, Luca stays in the past along with Azar. I think he will probably have the chance to let his family know he’s ok though. Maybe through Celebi (which is how he got stuck in the past in the first place.) He and Azar actually end up settling down in the past – getting jobs, integrating into society, even eventually falling in love with each other and starting a family. He’s sad that he can no longer see his mother and sister and the rest of his clan, but he’s pretty happy with his life as well. I think once she gets news that he’s safe and doing well, Clair will be fine with that. As long as Luca’s okay, that’s all that matters.