For All Mankind planted the seed of one changed event in its first episode which soon sprouted into an entire world where Russia pulled ahead of the United States in the now never-ending Space Race. But the series shined just as much of a light on private relationships and complex characters as it did the alternate history created by Battlestar Galactica showrunner Ron D. Moore.

When the second season opens on February 19, the Apple TV original picks up 9 years after the first season, and all its protagonists are dealing with a new host of issues. But the problems of the past remain, especially for Karen Baldwin (Shantel Van Santen, The Boys), who is still processing the death of her son a decade prior and how it changed her marriage to astronaut Ed (Joel Kinnaman, The Suicide Squad).

Related: 10 Reasons You Need To Watch For All Mankind

Van Santen spoke to Screen Rant about where Karen Baldwin  finds herself at the start of season 2, how she's bonded for like with some costars, and the very personal process she used to connect with a mother's grief.

Ed Baldwin puts his hand on Karen's cheek

In season two, For All Mankind jumps ahead nine years. What is it like for you as an actress to stepping into a new phase of Karen's life, while still carrying the loss of her son with you?

Shantel Van Santen: I felt two things at once. I first felt worried that we had missed these different chapters of what grief would have done, and how we find her where she's at.

In the midst of feeling that way, I started a journal where I would write my own memories I created for Karen. I would journal as though I was Karen. I've never told anybody this, but I actually read my grandmother's diary that she left me. My grandmother lost a son who was 14 years old way back when, and I read a lot of what she wrote, how she dealt with grief, and how she leaned on her face.

For me to fill in the gaps of those nine years was important, but it was also exciting. It was exciting to pick up where they had chosen. And to be honest, most stories we see about loss deal with the aftereffects right away. I don't know how many stories we've seen of couples and people nine years later, and how it still exists, and it lives in your bones and in every single heartbeat. I was worried that we would miss that, and that we wouldn't pay justice to the story. But I was very wrong.

When the first episode opens, Karen and Ed seem to be in a good place and their family has evolved. Can you talk about where they are as a couple when the season starts?

Shantel Van Santen: I think that being a mother and a nurturer and a caretaker is just in her bones. It's who and what Karen is, so no matter what she does, I think that she'll always relate to that part and need that to feel truly fulfilled. I also think she's discovering how to take care of herself for the first time, and what rings true for her. That's a little bit conflicting, and it feels pretty selfish as well, which can bring a lot of shame or guilt for somebody who's lived so many years for others in a program and a family.

There's a lot of dualities that are existing in this relationship with Ed that we're finally seeing in person, where we're in each other's faces and in each other's orbits and have our little life together. But is that truthful? Is that bringing us joy? What's not being said? I used to think that it was such a broken relationship that they had, having only face time from space. Now I think, after the pandemic, that we actually cut to the chase and get to the meat of what we need to talk about like that, versus when you're around somebody and you don't want to talk about everything all the time. It was a different relationship on so many levels.

And Joel is fantastic, so we just had a lot of fun playing around with discovering what our marriage is now and who we are.

Tracy comforts a sad Karen in For All Mankind

Speaking of the pandemic, you stopped production near the end of the season and then had to jump back in months later. Was that jarring?

Shantel Van Santen: We should block shoot, so we were right in the middle of the last block. We had started episode 9 and 10, and there's a scene that starts inside the house, and then we exit outside the house. We shot the part in the house and stopped in March because of the pandemic, and we came back in August to shoot outside. We have the Quarantine 15, so I'm like, "How is this gonna look the same?" We had lines from stress; there was a lot of things where I was like, "This is not gonna match."

And it was challenging, but even when not I'm shooting the show, the character never leaves me. I was actually really grateful for the time, because sometimes when I'm in it, I overthink things. The pandemic gave me the space to actually see the scenes in a very different manner. I remember running the scene leading up to doing it again, and I'm like, "Oh, my gosh. I understand what the scene is about now!"

I thought it was something so different before, because I was in this place with what was happening in my life. The ways that we inform the characters as actors is always going to be always different, because we approach it depending on where we are in our life.

I really like the dynamic between Karen and Tracy. Last season, we had those moments of Karen being jealous or maybe just unsure of Tracy's career choices, but now we see them in a different light despite only sporadic moments of supportive friendship. Can you talk about working with Sarah Jones on set?

Shantel Van Santen: That's an easy question. Because we call each other wifey; we are forever bonded. It literally makes me emotional, because going through the experience I went through in episode eight of season one, I would never have survived without her at my side. Our characters are of course bonded for life when you have experiences like that, but off screen, we're also bonded for life and we're extremely close.

But it's also interesting because you want to explore the things that really worked and you loved in season one, but there are other things that they choose to explore and there's reasoning behind it. I fully support our writers and think they're incredible. There are parts of our lives that that I missed, and I think the audience will too, but that's part of life. There are friends of mine that I've had forever, but you don't get to connect as much because they have kids and other things going on, and it's the evolution of your friendship. It's just different. It's still there, and the love is still there, but it's just different now.

In season one, I never viewed Karen as necessarily being jealous of Tracy. It just was so fear-based. She was afraid to lose her friends, she was afraid to lose her husband, and she was holding on so tightly to what she knew. Because if things changed, what would it look like? Most people are fearful - I know I am - of change. Change is a tough pill to swallow. That's why I think she held on so tightly and rigidly to what she knew, rather than being more open-minded.

More: For All Mankind Show Creators Explain Why Season 2's Time Jump is Necessary

For All Mankind premieres through Apple TV on February 19.