Always in our hearts. Always. Alan Rickman died at the age of 69 on Thursday, January 14. The British actor was privately battling cancer, according to The Guardian.

Rickman was best known for playing Professor Severus Snape in the Harry Potter movie franchise and Hans Gruber in Die Hard. His other notable credits included Sense and Sensibility, Galaxy Quest and the 2003 favorite Love Actually. He last voiced the Blue Caterpillar in Tim Burton's adventure fantasy Alice Through the Looking Glass, which hits theaters this year.

Rickman's Harry Potter costars, Emma Watson and Daniel Radcliffe, also posted about his death. The actors played Hermione Granger and Harry Potter opposite Rickman in all seven movies. "I'm very sad to hear about Alan today. I feel so lucky to have worked and spent time with such a special man and actor," Watson wrote via Facebook. "I'll really miss our conversations. RIP Alan. We love you."

Radcliffe, for his part, wrote a lengthy post on his Google+ page. "As an actor he was one of the first of the adults on Potter to treat me like a peer rather than a child," he wrote. "Working with him at such a formative age was incredibly important and I will carry the lessons he taught me for the rest of my life and career."

J.K. Rowling, who penned the best-selling books, wrote: "There are no words to express how shocked and devastated I am to hear of Alan Rickman's death. He was a magnificent actor & a wonderful man."

Emma Thompson paid tribute, too. The actress starred in several movies with Rickman, including Harry Potter, Sense and Sensibility and Love Actually. "Alan was my friend and so this is hard to write because I have just kissed him goodbye," she wrote, via Newsweek. "What I remember most in this moment of painful leave-taking is his humor, intelligence, wisdom and kindness. His capacity to fell you with a look or lift you with a word."

"He was the finest of actors and directors. I couldn’t wait to see what he was going to do with his face next," she continued. "I consider myself hugely privileged to have worked with him so many times and to have been directed by him."

Read more reactions below: