I'm not too keen on pet parent, seeing as the actual parent and grandparent of my youngest dog also reside at my house. While I personally prefer owner, I prefer parent to guardian, which has legal implications I am uncomfortable with. BTW, I may not be as attached as their moms were when the girls were baby puppies, but I'm pretty sure I'm more fond of the prima donna middle "child" than either her mom or her daughter are(who are BFFs with each other)