I believe you & I have the same John Bain in mind as the John Bain that you inquired about was Married in 1926 to Annie Sanders(Indiana )Clinton Ingram Sanders Bain.
I corresponded with one of Mr Bain's daughters for several years as Indiania is related to my family.And to answer your question I don't believe Mr Bain & Annie had children of their own.
I understand Mr.Bain raised some of The Dunnivans children.
As I understand Indiana had 2 Children buy her first marriage.