son getting married she doesnt want children he does. what can i say or should i just let him marry?

My oldest is getting married in 8 months. Although she has always joked about not wanting children, I now find out she is serious. She is a wonderful girl, and my son is very much in love. He does want children and says she is only joking about this. But when you talk to her she is very serious. I am worried my son will be very hurt and may end up in divorce. I would like to know if we can handle this before the wedding, or should I just let him marry and then be there to catch him and comfort him when he finds out the truth?