Child support and custody can be determined during the separation phase as part of a parenting agreement. This type of arrangement must be approved by a family law judge and can then be enforced by the state. Unless there is a compelling reason to change these arrangements, the terms and conditions decided upon during separation often become part of the final divorce decree. This is one reason for both parents to take the time to fully investigate their options and rights during the separation period to determine acceptable levels of child support. Custody is usually given to the mother and is difficult to change once it has been established. However, judges often grant joint custody to ex-spouses who have shown they can get along and make good joint decisions on behalf of their child.