I know a couple who wanted a child for a long time. The doctors told them they couldn't have one (I don't know the reasons).
So eventually they
adopted a boy.
About a year later they got a child of their own
With my Loa understanding of today I think they concentrated too much on the 'wanting'. After they had adopted the child they 'let go' of their wish - and *bam* it happened effortlessly.