For years in between Harry Potter installments, J.K. Rowling kept so much under wraps. She exerted tight control over the biggest literary juggernaut of our time, managing it with fierce pride, down to the last nondisclosure agreement. After that final book was released and the hype slowly died down, however, we’ve really gotten to know Jo Rowling, beyond the archetypal origin story of the single mom on government assistance. It turns out she is everything we could hope for in a world famous author-cum-celebrity.

Today, on the birthday that she shares with Harry Potter himself, some commentators will no doubt be praising her as perfect — but she’s not. She’s a bit messy, which makes me love her more. For instance, her post-Potter novels, including serious The Casual Vacancy and the Cormorant Strike novels under her Robert Galbraith pseudonym, have been a mixed bag, critically. They showcase her humor, energy and plotting skills and keen sense of social justice, while perhaps going overboard in being gritty and dark and even grotesque, because now, of course, she can do these things. I’m still hopeful that she can write an adult novel that balances it all, but it’s impressive to see her trying things in different genres and even temporarily shedding her fame to have a go at mystery-writing, anonymously.

Beyond that, she told us that Dumbledore was gay, a declaration that began as a controversial moment, and has ended up being an accepted, even beloved meme. She also gave an epic commencement speech at Harvard about failure, one I wish I’d heard as an undergraduate, which included her dropping this bit of grown-up muggle wisdom.

So given a Time Turner, I would tell my 21-year-old self that personal happiness lies in knowing that life is not a check-list of acquisition or achievement. Your qualifications, your CV, are not your life, though you will meet many people of my age and older who confuse the two. Life is difficult, and complicated, and beyond anyone’s total control, and the humility to know that will enable you to survive its vicissitudes.

But perhaps Rowlingis best beloved these days for her on-point Twitter game. She has mastered the art of the 140-character diss like no one else, and she uses it for fun, for feminist anti-racist work, and to continue to bring joy to her many legions fans.

There was this sally at a troll who was calling her sexist names:

And this recent defense of awful Serena Williams haters:

She went after the Westboro Baptist Church:

And also eviscerated Rupert Murdoch’s anti-Muslim nonsense, which was my personal favorite:

Her tweets show the same skill-set as her novels; humor, wit, a strong sense of right vs. wrong, and a playfulness of spirit. All this, and half of tomorrow’s brilliant millennial novelists will have cut their teeth writing Harry Potter fanfiction when they were tweens. An entire generation of kids whose values and tastes were helped by Harry Potter are now entering the world as adults, and watching Rowling send good-hearted ether across the internets.

It’s a pretty impressive legacy.