Colorado law uses gender-neutral presumptions of parentage, which can apply when a child is born during a marriage or when parents hold the child out as their own. Courts weigh multiple factors to resolve competing presumptions with the child’s best interests in mind. Assisted reproductive technology does not automatically defeat a presumption under the statute. Many families still pursue confirmatory steps like parentage orders to avoid issues if they travel or move. Early legal planning helps align birth records, parentage presumptions, and any later orders. The Uniform Parentage Act provisions explain these standards.