Sadly not that I can see, aside from some mentions in Magnimar/Varisia related publications. I think the best info on him though is probably from the two APs (or is it more...) he is in, though I do not own the Magnimar book, so could not comment on that one.
They actually released a mini of him though in the Lost Coast Pathfinder Battles series.
As for stats, I can't find any, but here is a link to custom NPCs. You could probably find the stats for a 9th level aristocrat and just use those as a quick template.
I believe there is some in the Rise of the Runelords books and the book on Magnimar.
Here is what I was able to pull up from the books I have, no mention of family really so that one's up to you:
"Haldmeer Grobaras, lord-mayor of Magnimar, is a bombastic and self-serving nobleman who sees his stewardship over the city as a reward for his hard work as an aristocrat and not as a service to his people. Normally, the plight of the poor isn't his concern-he has people who have people to take care of those problems.
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Since the establishment of a formal city government in 4608 AR, Magnimar has been led by two political bodies: the Council ofUshers and the Office of the LordMayor. When the city was established, this egalitarian arrangement was meant to ensure that no one person would have too powerful a voice in the city- state's governing. After more than a hundred years, however, this noble effort has become embroiled in officialism, paper shuffling, and the ambitions of its members. Undisputedly the most politically powerful person in Magnimar, Lord-Mayor Haldmeer Grobaras is a paunchy, self-serving politico more concerned with his own comforts than the needs of the underprivileged he hears so much about. Having managed Magnimar for many years, Grobaras half-heartedly handles the immediate needs of the city, indifferently settling matters relating to the distribution of city funds, use oft he city watch, and the concerns of countless citizens groups , all while welcoming bribery and lavish gifts. Although his dedication to the finest Chelish fashions and his numerous chins make the lordmayor's self-indulgent foppishness blatantly apparent, they hide a silver tongue and the private wealth to fulfill nearly any promise. While his station would have him uphold the mandates ofthe Council of Ushers, he often ignores such duties, proving more attentive to whether or not his personal declarations are enforced.
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As a city founded by those who refused to live under the reign of tyrant s , Magnimar has relatively few laws. From its barracks within the Arvensoar, the towering fortre s s of Magnimar's small military, the city watch patrols the length and breadth of the city-although Lord-Mayor Grobaras's decrees see that the richest quarters of the Summit receive the most attention. When the law falls into dis pute or cannot be meted out by the watch, quarrels are taken before the esteemed Justice Court."