Heath Ledger is still in the hearts of his loved ones a decade after his death.

The Joker actor’s ex-girlfriend, Naomi Watts, posted a bittersweet tribute for Ledger on Monday, Jan. 22, which marks the 10th year anniversary of his passing. On Instagram, Watts shared a photo of Ledger and said in the caption that she is “thinking about this beautiful soul.”

In 2011, Watts, who dated Ledger from 2002 to 2004, opened up about their relationship during an interview with More magazine. The actress revealed that while their relationship had not lasted very long, Ledger still made a big impact on her after they parted ways.

“We had a beautiful relationship, only a couple of years, but he was a man who was completely full of joy, and there was a lot of laughing and affection,” she said of the late “Dark Knight” star. “He was really a very special soul and made a great impact on my life. And a great actor, but I know there was so much more to come.”

Another actor who was deeply affected by the loss of Ledger is Jake Gyllenhaal, who starred with him in “Brokeback Mountain.” During a 2015 interview with NPR, Gyllenhaal said Ledger’s death helped him put things into perspective and appreciate his relationship with his movie co-stars more.

“I think losing Heath and being a part of a family that was something like the movie, the movie we all made together, makes you see that, makes you appreciate that and hopefully moves you away from the things that really don't matter to the things that do . I’m trying to have relationships that are as real as they possibly can be on a movie set, be close to people because I know that it’s precious,” he admitted.

Aside from Watts, Ledger’s family, especially his older sister, Kate Ledger, also make sure that the actor is not forgotten.

Kate recently opened up about her brother and his impact on their lives to WHO. She explained that though her kids had been very young when he died of accidental overdose at 28, they still got to know their uncle through the stories she tells about him.

“Heath is hugely important in the lives of my children . There’s not a day that goes by that we don’t share stories or talk about him. He is very much alive in our house ,” she said (via People).

One way her children has gottent to know their uncle is through his movies and shows. “It’s especially difficult to see his moving images on screen and hear his voice—something which we as a family have had to learn to cope with constantly,” Kate revealed . “But it’s a blessing that we have all the images and footage so that we can share a part of him with our girls.”

Kate and the rest of their family also stay in touch with Ledger’s ex-wife, Michelle Williams, and their Matilda, who is now 12. “We keep in constant contact with Michelle and Matilda and visit frequently,” Kate said. “She is an amazing girl and a source of delight to us all.”