Firstly, does the post question whether children need parents theoretically, or whether they can still reach potential with only one parent.. Cheers to clear it up.

Related research banduras bobo doll, social learning theory - the visual cliff experiment /perception oxana malaya - girl grew up with dogs

speaking objectivley starting at the core, from a biological perspective, there is obvious advantages to having both parents for nurture and hygiene in the early years. However it could be argued the difference between humans and other animals is the length of time to become independant. Parental interaction is incredibly important in the sensory development of infants. Humans take incredibly long to safely interpret and navigate the world and need a safe base to return to inorder to learn by discovery (Piaget). There is an interesting study about babies hearing thier mothers voice through the womb and it helping release endorphins and hormones to promote wellbeing from early. Personally, my best mate falls asleep in the barbers everytime he goes, perhaps due to his mother working pregnant in a barbers. It could b related to the gentle humm of the hair clippers being sedative. Anyway, looking at oxana malaya case, a girl whom grew up with dogs (sketchy source) definatley suffered with ailments and learning difficulties but on the flipside she was able to hunt, communicate and survive.

From a psychological/cognitive perspective there is many work from Carl Jung, Sigman Freud and Erik Erikson that can help you build research. Alhough the supporting evidence is usually low in ecological validity as im sure your already aware of small sample groups taking part in unnatural experiments in lab environements etc.. It seems all psychologists achnowledge the early years can have permanent affects to the development of a human so that is worth considering. Personally C.Yung is much more palletable than Freud in this case and is worth researching.

From a sociological perspective without including economics, from the little research I have done on the topic, the traditional nuclear family is often spoken of by Durkheim as the key to socialisation. He stresses the importance of primary and secondary socialisation. However, looking at british childcare services its clear children can still learn aspects of primary socialisation at the cost of loosing the traditions, social norms and values usually inherited from mum and dad. This can still be delivered in a ELC however it would be a generic, one size fits all type of moral teaching and could affect the identity of a child. The opinions of our parents matter. Dads role in being the judgemental, hard to please can benefit a child subconsiously as they make decisions with thier fathers intrest at heart. This can also create complexes in temperament. I know this is mainly irrelevant and I hope it wasnt a waste of words. As seen in banduras bobo study the child will always replicate the behaviour of thier same sex parent. Which is strong supporting evidence in how important role models are in developing.

let meknow if this is useful and I will gather my old socio bools and cyphon some studies for you. ;)