Parental Responsibility
Parental Responsibility (PR) is the key to the Children Act 1989. Any adult who has PR can make any decision about a child's welfare. If there is more than one such person, any of them can decide : if they don't agree, then a Court may have to decide for them.
The mother of a child will always have PR and cannot lose it unless the child is adopted. The father will have PR if he was married to the mother or if he was on the birth certificate (children born from 1st December 2003). If he does not have PR, it can be given to him by agreement for which there is a special form that has to be signed at Court. If the mother does not agree he can apply to a Court to give him PR. The general rule is that the Court will only refuse PR to the natural father in very exeptional circumstances.
PR can, however, be given to other adults in various ways, thus enabling them to act as a parent.
If a Residence Order is made, e.g. to a grandparent or other relative, they will have PR for as long as the order is in existence.
If one parent remarries or enters into a civil partnership, either they or their new spouse or partner can apply for PR but a Court would have to decide the issue unless everybody was in agreement.
Any parent can also "delegate" parental responsibility to any other person by letter or otherwise - this is incredibly vague and has not bet been defined by any appeal decision.