1) merely because mother is given custody does not mean she can give child in adoption to you without father consent
2) section 5 of HAMA provides tha adoption made in contravention of provisions of act are void
3) The adoption is not valid unless the person giving in adoption has the capacity to do so and the adoption is made in compliance with the conditions mentioned in Chapter II of the HAMA, which would include the condition mentioned in the proviso to Section 9(2) of the said Act.
3)
"9. Persons capable of giving in adoption.-
(1) No person except the father or mother or the guardian of a child shall have the capacity to give the child in adoption.
(2) Subject to the provisions of sub-section (4), the father or the mother, if alive, shall have equal right to give a son or daughter in adoption:
Provided that such right shall not be exercised by either of them save with the consent of the other unless one of them has completely and finally renounced the word or has ceased to be a Hindu or has been declared by a court of competent jurisdiction to be of unsound mind."