he may select his own guardian, subject to the approval of the district
court of the county where his parents, or either of them resides; or, if
such minor is living separate and apart from his parents, the district
court of the county where he resides has jurisdiction. [§3435.]

[Sidenote: Powers.]

Guardians of the persons of minors have the same power and control over
them that parents would have if living. [§3440.]

[Sidenote: Duties.]

Guardians of the property of minors must prosecute and defend for their
wards. They must also in other respects manage their interests under the
direction of the court. They may thus lease their lands or loan their
money during their minority, and may do all other acts which the court
may deem for the benefit of the ward. [§3441.] All power of the guardian
over the estate of his ward is derived from the appointment of the
court, but an appointment as guardian will not authorize a sale of
property, nor an investment or disposal of money belonging to the ward,
without a special order of the court. All expenses for the education and
maintenance of the ward must be kept within the income of his estate. If
this should not be sufficient the principal may be resorted to, but not
without an order of the court. All transactions between guardian and
ward, where the former has secured an apparent advantage, by way of
gift, or contract or settlement, will be presumed to have been the
result of undue influence, and will be set aside by a court of equity,
unless it can be shown that they were made in good faith and for a fair
and valuable consideration.