(a)in the case of an illegitimate child, no person shall, as father of such child, be required to give information under this Act concerning the birth of such child, and the Registrar shall not enter in the register the name of any person as father of such child, except at the joint request of the mother and the person acknowledging himself to be the father of such child, and such person shall, in such case, sign the register together with the mother,
