Dear Reena,
This is really a grey area when it comes to adoption law. Earlier a widow could adopt could not adopt in her own right but only to her husband, the child was deemed to have been adopted by husband before his death. The child automatically became member of deceased father's coparcenory. As regards permission to adopt by husband before death or his relatives is concerned there are divergent views some high courts have pressed it's need while some have ignored it - it would depend on where the case pertains to. This position is incompatible with present act of 1956, however still the Supreme Court has in 2-3 decisions allowed widow to adopt to her husband in the 1960s. Disclose exact facts alongwith your locus on this to discuss further on these complex issues.
Regards,
Bharat