California Family Code 213 provides as follows:
(a) In a hearing on an order to show cause, or on a modification thereof, or in a hearing on a motion, other than for contempt, the responding party may seek affirmative relief alternative to that requested by the moving party, on the same issues raised by the moving party, by filing a responsive declaration within the time set by statute or rules of court.
(b) This section applies in any of the following proceedings:
(1) A proceeding for dissolution of marriage, for nullity of marriage, or for legal separation of the parties.
(2) A proceeding relating to a protective order described in Section 6218.
(3) Any other proceeding in which there is at issue the visitation, custody, or support of a child.
In other words, when a request is made that the court make orders, there is always the risk that the other party can request an order that favors them in the response, which the court is authorized to consider.