Little Brady Dunn probably doesn't know it yet, but his puppy, Astro, is destined to become more than a best friend.

He might become a lifesaver.

For now, the poodle/golden retriever mix is Brady's new pet. But for his parents, White Sox designated hitter Adam Dunn and wife Rachel, Astro is the newest option to help keep things normal for their oldest child, who has epilepsy.

Only 7 months old, Astro already is in training to be a medical-assistance dog who will be 5-year-old Brady's "shadow."