Leiana should use a possessive pronoun when referring to the car that belongs to her family. A possessive pronoun indicates ownership. The best pronoun to use in this case would be "our," as it shows that the car belongs to Leiana's family collectively.
For example, she might write, "On our trip, we packed snacks into our car." Here, "our" clearly indicates that the car is part of the family's belongings. Using "our" helps convey a sense of togetherness and shared experience.