But how was that dynamic created behind the scenes?
EW sat down with Leigh to get her take on the journey that Alex has made this season.
ENTERTAINMENT WEEKLY: Lets go back to when you first learned Alex would be coming out.

Robert Falconer /The CW
They had this funny little smile on their face, Im like, Whats going on?
Theyre like, Well, so this season, Alex is gay.
I was like, Oh,what?

Bettina Strauss/The CW
Thats how we wanted to approach it.
I just want to ensure that this is very respectful and tasteful and being done with sensitivity.
Thats what they were all about, too.

Dean Buscher/The CW
We had an open dialogue about stuff.
We had a conversation with Greg Berlanti about it.
He was probably anticipating about a 20-minute conversation; it was almost an hour and a half.

Randy Holmes/ABC
Now theyre just living it up.
I think its just beautiful, and Im just so grateful to be a part of this.
I take it very seriously because its incredibly important for it to be done right.

Nathan West/Instagram
What was casting for Maggie like?
We were in Canada at that point.
Im very particular about whos on our set, just because weve got a vibe.
This was incredibly important to me because I knew how delicately this was going to be treated.
They sent up the audition tapes for three girls.
I looked them over, my husband looked them over with me.
Hes like, Im going to see to it you get a good girl!
I was like, All right, honey.
Its pretty great he picked out my girlfriend before I did.
I said, All right, Im going to test her in the room to see how it goes.
She was the second one to come in after the first girl who came in they were all lovely.
Lifes too short, I dont have time for B.S.
We get through the whole process, and it seemed like everybody was on the same page.
I wrote to Greg, I wrote to Andrew, I wrote to Peter Roth.
Get her for me.
He was just like, Chyler, I cant believe you emailed me.
I was like, No, for real.
Hes like, I totally see it, I get it, shes lovely and wonderful.
Then I get the call that she was going to do it.
I got her information.
I literally hunted her down.
It sounds really creepy, actually.Hmm.
Shes like, I love it.
It was pretty awesome.
But we texted each other quite a few times and went back and forth, tried bonding that way.
But when she came on set, it was like, Oh, okay.
Its one of those times where you meet somebody and it feels like youve known them forever.
Its the same thing.
We were very similar in a lot of ways, so it was just easy.
Thats what I really appreciate about it; we didnt have to manufacture something.
Sometimes its great, sometimes its awful, and you gotta do what you gotta do.
But this was one of those cases where shes a special girl and we have a cool bond.
and I felt uncomfortable, because I hadnt walked in Alexs shoes from that side of her.
It was challenging, though, for sure.
Okay, I feel things really intensely, just use it.
So all the stuff in the bar, I really felt it.
Thats something that people have been relating to the most because its honest.
Im not trying to [whispers] bullshit people.
It was challenging in all the best ways.
There were moments along the way, like, Okay, take a deep breath and go for it.
Its not me, its about what were doing thats more important than anything.
Now that weve gotten a little bit more of Maggies background, whats next for the couple?
Maggies been in prior relationships, and Alex hasnt really been a part of it.
That was the whole happy, bubbly thing when she came out.
Ahh, this is amazing!
Maggie did want to protect Alex in so many different ways.
Once she realizes, its not about protecting, its about being honest.
Alex is kind of like, Oh, lets go chat her up.
I think theres profiling thing thats going on.
So theres great development in that.
Do you still watchGreys Anatomy?I have not seen it since I died.
Im so grateful for that time, but afterward, it was like letting it go.
I never really watch shows anyway.
I dont really have much time for TV.
I watchSupergirland I love it, its amazing.
Thats where I am now in my life, so that is what Im investing my time in.
After leavingGreys, IleftGreys, like let it go.
I mean, I cried for hours after we had finished filming, just letting it go.
Its letting go a part of yourself, but I think it was handled really well.
I thought it was a beautiful way to go.
If youre going to die, die under a fuselage of a plane!
Why not, right?
I dont even know!
I mean, her sister has all these amazing powers.
Maybe the gift of healing?
Its such a cool angle to come from, that you dont have to have superpowers to become powerful.
I think all the people that are on the show right now cover all the bases.
What would be a really good power?
Maybe making people trip?
Maybe thats a good one.
Telekinesis, lets go with that.
Or Tie your shoelaces together!
That kind of stuff.
Give you a wedgie!
Sounds like a solid use of powers.Absolutely.
Those are really excellent examples.
Wow, I just turned into my 13-year-old son.
I wont even mention it because then people will look for it.
We all have skeletons in the closet, dont we?
Yeah, theres plenty that will just remain there.
You didnt end up singing in theSupergirl/Flashmusical crossover,but you did singwith your husband.
It was really a love letter to me, for me, about me.
Its part of who we are and where were at in our life.
It was our way of saying, Were together even when were not together.
Its a very poetic way to go about it.
I was like, Absolutely, I would love to do that.
I love singing with him.We work really well together in that side of our relationship.
It really was an opportunity to bring in something new.
If you’re free to do something new and keep things fresh and alive, lets do that.
Theyre heartbreaking, but theyre inspiring at the same time.
Theres thisyoung ladythat put out this idea of saying, Heres our appreciation for Chyler and where shes at.
My husband and I have an organization calledCharity Pulse.
Its something Ive always been insecure about.
Its a lot like Alexs story; Ive been telling my story.
Last night Im going to cry I was reading them, and its so moving.
Its so powerful, and its just amazing to know.
I appreciate it tremendously, people putting me in a position to share.
Im a mom at heart and I always have been.
I feel like I have millions of kids now, and its amazing.
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