Does the father have money to make taking him to court worthwhile?
In WA, parents who are divorcing or otherwise going through a family law proceeding may be ordered to pay post secondary education support for their children.
If the sister has the academic ability and desire to go to school and the parents have the financial ability, someone should look into getting a court order for post secondary education support for the sister if there is not already such an order.
What options are available to your family depend on your specific facts. Your mother or you may want to review the facts and options with an attorney.
you can file a third-party custody petition and try to get custody of your sister.
unfortunately, you will be in an uphill battle against the father. in a custody battle between 2 parents, custody is supposed to go to the parent based on the child's best interest. however, in a custody battle between a parent and a non-parent, custody goes to the parent unless: 1) the parent is unfit, or 2) placement with the parent would cause actual harm to the child's growth and development.
also, to prove adequate cause to hear the petition, you must prove: 1) the child is not in the physical custody of either parent, or 2) the parent(s) are unfit.
a statement from you mother supporting your 3rd party custody petition for your sister would help you tremendously.
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