Short answer. Yes to both. Rule 3, Section 5 of the Rules of Court provides that a minor may sue or be sued, but only with the assistance of a father, mother, or guardian; if the minor has none, a guardian ad litem — a representative appointed for the litigation — supplies that assistance.
What the law says
A minor or a person alleged to be incompetent, may sue or be sued, with the assistance of his father, mother, guardian, or if he has none, a guardian ad litem.
Rule 3, Section 5 — Minor or incompetent persons. Read the full provision →
Assistance, not substitution
Read the section closely: the minor may sue or be sued, with the assistance of his father, mother, guardian, or if he has none, a guardian ad litem. The action belongs to the child. The parent or guardian assists — the case is brought in the minor's name for the minor's rights, and any recovery is the minor's, not the assisting adult's. This is the assumption to correct at the outset: a parent suing over a child's injury is not the claimant; the child is, with the parent standing alongside to supply what the child's age withholds — the capacity to litigate.
Who supplies the assistance
The section lists the assistants: father, mother, guardian — and, if he has none, a guardian ad litem. A guardian ad litem is a guardian for the litigation only; the mechanism exists so that no minor is ever shut out of court, or left undefended in one, merely because no parent or general guardian is available. The same structure works in both directions. A minor plaintiff needs the assistance to bring the claim; a minor defendant needs it so the suit against the child can proceed and be fairly defended.
The rule also covers alleged incompetents
Section 5 pairs the minor with a person alleged to be incompetent. The word doing the work there is alleged — the section extends the same protective mechanism of assisted litigation to a person whose competence is in question, not only to one already under guardianship. For families this matters where an elderly or ailing relative must sue or answer a suit: the same options — assistance by a father, mother or guardian, or a guardian ad litem where there is none — keep the case moving without the person litigating alone.
What to sort out before filing
If your child has a claim, the practical question is who will assist and in what capacity: a parent can act directly, but where parents are absent, deceased, or themselves adverse to the child's interest, a guardian ad litem is the fit, and the need should be raised with the court early. If your child has been served with a suit, do not ignore it on the theory that a minor cannot be sued; the section says the opposite. In both directions, the child's birth certificate and proof of the assisting adult's relationship are the first documents a lawyer will ask for.