I am a law school graduate. What I offer is mere information, not to be construed as forming an attorney client relationship.
Lots of questions. You get a family law attorney to bring a motion to amend the order based on new circumstances, the mom's disregard of the original court order, your caretaking abilities and possible child endangerment issues.
Venue/jurisdiction might be changed based on convenience to parties, other factors, once the case is originally filed. Then your attorney will make a pre-trial motion to change venue. THis may or may not be granted.
As to the child's age of giving his/her opinion of where he/she wants to live, this is just one factor the court will take consideration. The court will take into account many factors to determine the child's best interest. In California, that age is:
3042. (a) If a child is of sufficient age and capacity to reason so
as to form an intelligent preference as to custody, the court shall
consider and give due weight to the wishes of the child in making an
order granting or modifying custody.
(b) In addition to the requirements of subdivision (b) of Section
765 of the Evidence Code, the court shall control the examination of
the child witness so as to protect the best interests of the child.
The court may preclude the calling of the child as a witness where
the best interests of the child so dictate and may provide
alternative means of obtaining information regarding the child's
preferences.
3011. In making a determination of the best interest of the child
in a proceeding described in Section 3021, the court shall, among any
other factors it finds relevant, consider all of the following:
(a) The health, safety, and welfare of the child.
(b) Any history of abuse by one parent or any other person seeking
custody against any of the following:
(1) Any child to whom he or she is related by blood or affinity or
with whom he or she has had a caretaking relationship, no matter how
temporary.
(2) The other parent.
(3) A parent, current spouse, or cohabitant, of the parent or
person seeking custody, or a person with whom the parent or person
seeking custody has a dating or engagement relationship.
As a prerequisite to the consideration of allegations of abuse,
the court may require substantial independent corroboration,
including, but not limited to, written reports by law enforcement
agencies, child protective services or other social welfare agencies,
courts, medical facilities, or other public agencies or private
nonprofit organizations providing services to victims of sexual
assault or domestic violence. As used in this subdivision, "abuse
against a child" means "child abuse" as defined in Section 11165.6 of
the Penal Code and abuse against any of the other persons described
in paragraph (2) or (3) means "abuse" as defined in Section 6203 of
this code.
(c) The nature and amount of contact with both parents, except as
provided in Section 3046.
(d) The habitual or continual illegal use of controlled substances
or habitual or continual abuse of alcohol by either parent. Before
considering these allegations, the court may first require
independent corroboration, including, but not limited to, written
reports from law enforcement agencies, courts, probation departments,
social welfare agencies, medical facilities, rehabilitation
facilities, or other public agencies or nonprofit organizations
providing drug and alcohol abuse services. As used in this
subdivision, "controlled substances" has the same meaning as defined
in the California Uniform Controlled Substances Act, Division 10
(commencing with Section 11000) of the Health and Safety Code.
(e) (1) Where allegations about a parent pursuant to subdivision
(b) or (d) have been brought to the attention of the court in the
current proceeding, and the court makes an order for sole or joint
custody to that parent, the court shall state its reasons in writing
or on the record. In these circumstances, the court shall ensure
that any order regarding custody or visitation is specific as to
time, day, place, and manner of transfer of the child as set forth in
subdivision (b) of Section 6323.
(2) The provisions of this subdivision shall not apply if the
parties stipulate in writing or on the record regarding custody or
visitation.