I wonder if Guinness keeps track of this sort of thing. An Indiana newspaper reports that Hunter Joseph Collins, born in August, has 15 grandparents living. This includes three five-generation sets.
The first set of five generations involves Hunter, his father Andrew Stroud, his grandmother Becky Stroud, his great-grandmother Vickie Barnes and his great-great-grandfather Claude Sparks. Another set is Hunter, his mother Kimberly Collins, his grandfather Jimmy Collins, his great-grandfather Loyd Collins, and his great-great grandmother Lottie Collins. The third three-generation set is Hunter, his mother Kimberly Collins, his grandfather Jimmy Collins, his great-grandmother Dorothy Collins and his great-great grandmother Joan Shotts. [Link]