Lupita Nyong'o says leaning on her castmates for support was the "only way to go forward" while filming "Black Panther: Wakanda Forever."

During an appearance on "Good Morning America" Tuesday, the actress, who reprises her role as Nakia in the film -- the sequel to Marvel's 2018 hit "Black Panther" -- spoke about how the "Black Panther" family came together in the wake of Chadwick Boseman's death.

Nyong'o described the first day back on set together for the sequel as "hollow."

"It was very evident that he was missing and we were all feeling it, but also, we had each other," she explained. "So we were able to lean into each other."

She continued, "It was actually the only way to go forward, I imagine, was to lean into it and be there for each other. It was good to be making this with a bunch of people who knew him, who had experienced his light and his love and so we could commiserate and really lean on each other in the process."

Nyong'o said that the characters in the film are also united in their grief over the loss of T'Challa.

"When someone like that passes away, it has an effect on everyone around them, and so we see how different characters are dealing in different ways," she said. "Nakia is a little bit more advanced in the stages of grief than I was when I made this film so it was actually very therapeutic to work on this role to get through my grief."

Danai Gurira, who reprises her role as Okoye in the sequel, said they "needed to be" there for each other while filming.

"There was a journey we were taking -- there was a journey of grief and loss that we were navigating as we did this to honor our brother," she said while appearing on "GMA" Monday.

"You never knew when and how you would need more support ... and being around one another was the key thing," she continued. "Sometimes it was a day you were there for someone, sometimes someone was there for you."

She said she also found they supported one another by "enjoying each other's work."

"I remember being on set sometimes when Letitia [Wright, who plays T'Challa's younger sister Shuri,] was doing a scene and I wasn't shooting that day but it was just about being there and triumphing with her triumphs," Gurira explained. "Because watching what she was doing that day was giving me joy and so just to be there and experience the film from all the ways it was coming together was really also very nurturing."

The film's director Ryan Coogler also opened up on Monday about having to rewrite the script of the sequel following Boseman's death.

He said he had a "phenomenal team" to help him throughout the process.

"I had a co-writer who was great, Joe Robert Cole, great producers, Nate Moore and Kevin Feige -- they were all supportive," he said. "And what was great about the first film, we formed a family so I had a good idea of what folks would be willing to do and not willing to do."

He continued, "These are all very strong-minded people, like Danai, and they don't do things if it doesn't have integrity or if they don't think they can pull it off. So I just thought about that and thought about what would honor Chad the best, what he would want us to do, what would make sense and we just worked at it and tried to make something that people could put their best into and make something for our audience."

The two also revealed their own three words to describe the sequel: Coogler's included "love," "life" and "hope," while Gurira's included "epic," "transformative" and "healing."

"Black Panther: Wakanda Forever" opens in theaters Nov. 11.

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