Minor with a Dual Citizenship, Schengen Visa

[JERRY787]

The Case:

Mother S.E. Asian, Father European, not married and also after several arguments, they have no more sentimental or whatever relationship at all, the child stay with the mother which refuse to show to the father even without any court order.

- The child has born on a third Asian country (means not at country of the mother) on the third country Birth Certificate has been registered only the mother name, no father name.

- 3 months later, the mother and the father officially registered the child at the embassy of the European father, practically making the infant first an European citizen

- 6 months after the mother went back to her own S.E. Country registered the child without recording who is the father.

- the father obtained a European passport for the child, so now the child has 2 passports, indeed in Asia is using the Asian passport.

- now the mother wish to relocate to Europe with the new boyfriend from east europe within the Schengen Visa treaty, probably marrying him and will ask such embassy to issue the visa as her child.

Note:
i know for sure that if there is no court order for custody only to the mother, practically must have the approval of both parents, but of course if she lie and declare no father, submitting such certificate, she will obtain the visa as the consulate where she may apply may don't know the true facts.

indeed i heard and that is my question :
-that there is a clause on the Schengen visa rules that a child minor of age with dual citizenship can not use the non european passport for require the schengen visa, as the child shall enter with the European passport within the European union.

anyone one here is aware of such rule ?
is so , any hint where i may find such reference online ?
or
anyone knows where i can find the full details for Schengen visa rules and requirements, so i can download it and study it ?

thank you in advance for your help