I think it is a bit misleading to say what will come of the nest generation if they are of a mixed background.
The nearest that humans can come to God is through love; sucha pyar. If you love someone do not worry about there faith, colour, etc.
Sikhism is about Truth in all things. The human heart will always respond to the beauty of truth. People can make their own decisions as to their faith.
If God wills sikhism may last or dissapear. But Truth, sachai, is always there.
JS
***************
Reply
***************
Very nicely put. Truth will always be has always been. Of course there will be problems in any inter faith or inter race relationship. There could be problems in a Sikh relationship nothing is mutually exclusive. Thank You for your words Jaskooner S. ji. Sat Nam.