S. Juan Macias, one of my patrons.*
I'm serious: So what? If a kid says he is spiritual but not religious he is probably on a quest. Meet him there. Greet him there. Speak to him there of all the cool mysticism and spiritual treasures of Catholic spirituality. Tell him about the mystics, speak to him about the holy mysteries. Make yourself, your faith, your love, so attractive that he might fall in love with Jesus Christ.
So many people make such a big deal of this spiritual but not religious thing. I was spiritual but not religious for a time. You are misguided and blind guides, if you cannot perceive that a soul is on its course, its journey, its pilgrimage. Do not impose your fears and prejudice upon such innocence. Neither should you disturb ... rouse love before its time. Love attracts... make Love loved.
*S. John Macias, feast September 18. Years ago I sent to Rome for first class relics of St. John, St. Martin, and St. Rose, all mystics and humble lay saints from Lima, Peru, each devoted to the Infant Jesus. I waited months and months without hearing a word; I had also sent a generous donation, so I half expected some sort of acknowledgement. Nothing came. Then after praying to St. John I had a dream one night. In it he showed me the nuns who assemble relics in Rome, and let me know the relics were being prepared and would be sent to me shortly. A few days later, the relics arrived from the same convent of nuns I had seen in the dream.