you could review Elder Bednar's talk "Things as they really are." Hopefully they are having a good time, and you can talk about the wonder of world in which we live, and the reality thats exists in friendship, brotherhood, and family. And warn them of the distortions of virtual reality.

https://www.lds.org/ensign/2010/06/things-as-they-really-are?lang=eng

Consider again the example I mentioned earlier of a young couple recently married in the house of the Lord. An immature or misguided spouse may devote an inordinate amount of time to playing video games, chatting online, or in other ways allowing the digital to dominate things as they really are. Initially the investment of time may seem relatively harmless, rationalized as a few minutes of needed relief from the demands of a hectic daily schedule. But important opportunities are missed for developing and improving interpersonal skills, for laughing and crying together, and for creating a rich and enduring bond of emotional intimacy. Progressively, seemingly innocent entertainment can become a form of pernicious enslavement.

To feel the warmth of a tender hug from an eternal companion or to see the sincerity in the eyes of another person as testimony is shared—all of these things experienced as they really are through the instrument of our physical body—could be sacrificed for a high-fidelity fantasy that has no lasting value. If you and I are not vigilant, we can become “past feeling” (1 Nephi 17:45), as did Laman and Lemuel long ago.