Re: Is Minato son of Tsunade? Where is Naruto's Grandparents?
Umm, actually when it comes to age thing. Tsunade is 50 (51) when the series starts, when Naruto was 12. so 50-12= 38 Minato was in his late 20s early 30s when he died. 38-28=10 I'm sorry if you don't know anything of a female's biology but women can't have babies when they haven' even start menstruating. Also like have said before I don't think the creator of Naruto would have people have kids when they are still teenagers.
When it comes to the grandparents, I think Minato was an orphan (or at least that's the jist of how I see, either that or I have been reading too many fanfics lately.) On Kushina's side who knows about the family on that side.