They are in the marketplace in the Caldera when it happens the first time. Azula hates this place. It smells like animals and dirty water and there are so many people who gawk openly and try to press trinkets on her that she does not need or want, even if she does not have to pay for them.
Ty Lee, on the other hand, loves it. She is the reason they join Zuko every time he decides to make an appearance among the common people.
"Azula, look at this!" she calls. She is holding up a gold pocket watch engraved with a spindly flower with some difficulty, given the number of other new possessions her arms are laden with. "Isn't it pretty?"
Azula squints at it. "It's broken. It's not even ticking."
Ty Lee narrows her eyes for a moment and then shrugs. "Oh well, it's the looks that count."
The vendors love Shinzei and Izumi. Izumi is skipping along beside her mother wearing a new headdress that looks like the homemade version of what Ty Lee wore when they were married and Shinzei is eating fire flakes out of a paper bag, cinnamon stuck to her lips. Her fingers twitch rhythmically against the bag and she bounces on the balls of her feet with each step, but her eyes are getting less focused, and Azula thinks she might be hiding how tired she is. She is only four, after all. She cannot be expected to keep up with the adults and Izumi, even if Azula was at that age.
"Princess!" a middle-aged women crows. Izumi looks back hopefully, but the woman lunges at Shinzei, holding a raggedy stuffed koala sheep in front of her.
"No, take this one!" a young man with a patchy mustache falls to his knees on Shinzei's other side, waving a patched tigerdillo in front of her face. It is not uncommon for the vendors to compete for their attention. Mai and Izumi are regularly given choices they did not ask for. It happens to Ty Lee less often, but she revels in it when it does. It has never happened to Shinzei before because usually Ty Lee or one of the guards is carrying her, and Azula does not expect her to make much of it. She expects her to choose one, or perhaps grab both as Azula surely would have done, had her father allowed her to own peasant toys as a child.
What she does not expect is the scream that cuts through the crowd.
Shinzei is not a loud child. She did not even speak until a year and a half ago, but when Azula looks over, she is crouched on the ground, her hands pressed against her face, crying out like someone is holding a hot iron to her skin.
The guards are on the vendors within second, pulling them away, holding the rest of the crowd back. The stuffed koala sheep lies stranded on the street.
"Shinzei!" Ty Lee pushes the guards out of the way, falls to her knees, and attempts to wrap her daughter in her arms, but Shinzei only screams louder and rocks harder.
"She doesn't want to be touched!" Azula pulls her wife away. Ty Lee is in tears, and Azula tightens her arms around her waist as their daughter wails. Izumi clutches onto Mai's robe, her eyes wide. Zuko whispers something to a guard and he disappears into the now-silent crowd, probably to summon the royal physician.
Shinzei's screams begin to subside, making way for quiet sobs. Azula keep ahold of Ty Lee. She has stopped struggling, but Azula does not think it will help matters if she tries to jump on their daughter again. Ty Lee likes to give comfort through physical contact, but that is rarely what Shinzei wants and obviously not what she needs right now.
A break in the crowd forms, and a moment later, the guard appears with three others carrying a palanquin. Azula did not think it was possible for her brother to do something so right.
She lets go of Ty Lee, who now seems completely paralyzed, and crawls toward her daughter.
"Shinzei," she whispers. "Shinzei."
Shinzei's head snaps toward her, though her eye look over her right shoulder.
"Do you want to go home?"
Shinzei folds her hands in front of her body and nods.
"There's a palanquin here for you."
Shinzei glances behind her, but it takes her a moment to start to move, like she cannot remember how to work her body. She curls up inside the palanquin and Azula pulls the curtain closed behind her.
She holds her arm out for her wife. Ty Lee folds herself into Azula's side and they follow their daughter back to the palace on foot.
"Am I sick?" Shinzei asks them that night as Ty Lee tucks her into bed and Azula watches.
"The physician said there's nothing wrong with you," Ty Lee tells her. Their daughter has seemed better since they arrived back at the palace. Exhausted perhaps, but better. She is clutching the ratty stuffed koala otter that started this mess. Zuko picked it up and brought it back for her, very much against Azula's wishes, and now Shinzei does not want to let it go.
"It was scary," she whispers.
Ty Lee lies down next to her, careful to keep her distance, because even at her young age, Shinzei does not like to be touched unless she is the one who initiated it. Azula takes the seat that she vacated.
"Do you want to hear a secret?" Ty Lee asks, and Shinzei nods. "I was scared too."
"I was scared too." Shinzei's eyes widen in surprise. "Why?"
"Because I love you so much."
"Oh." Shinzei looks away and says nothing else. She has never returned Ty Lee's sentiment, or Azula's on the rare occasion that it comes from her, and she knows that it concerns her wife, but Azula very rarely utters those words herself. She knows that never telling a person you love them does not mean you don't.
"Do you feel okay now?" Ty Lee asks. She eases her body toward Shinzei but is careful not to touch her. Azula takes her wife's hand instead and Ty Lee smiles at her.
"I guess," Shinzei mutters.
"Are you tired?" Azula asks. "Do you want us to leave?"
The four-year-old nods. Azula is not good at parenting, but she is somehow not terrible at knowing what her daughter needs when she is distressed.
Azula stands up and leads her reluctant wife out of the room. "Do you think she'll be okay?" Ty Lee whispers as Azula closes the door behind them.
"You saw her. You heard the physician. She's fine."
"Azula, that's not what I mean." Ty Lee's voice pleads at her. "Do you think something happened to her or… something?"
"What could have possibly happened?" Azula asks. "You're with her all the time. It was a tantrum. She is four."
"It was not a tantrum, Azula!" Ty Lee cries. "Did you see that?" Her eyes are gathering moisture and her breaths are rapidly beginning to quicken. "This is our daughter! You can't just pretend nothing's wrong and hope it will go away!"
Azula sighs. "I know it wasn't a tantrum."
Ty Lee crosses her arms in confusion. "Well, then…"
Azula stops walking and leans back against the hallway wall. "I said that because I'm concerned."
"Well, so am I. That's what I'm trying to talk to you about—"
"I'm concerned that she got this from me," Azula mutters through clenched teeth. She does not meet Ty Lee's eyes. She does not look at her at all. She was so intent on giving birth to their child so that the blood of the Royal Family would run through her veins and because Ty Lee had already done so much for her, but in hindsight that all seems selfish when there was this sort of risk. Ty Lee has always been in perfect health and Azula spent five years barely hanging on to her sanity. "I'm concerned that the same thing that's wrong with me is wrong with her and it's because I was the one who had her."
"Oh, Azula," Ty Lee pulls her into a hug that Azula wants to pull out of so that Ty Lee will know she does not need to be comforted, but she is trapped between her wife's body and the wall. "I mean, sometimes you've had breakdowns like that, but only when you weren't okay to begin with. It's never been out of the blue like that. I'm sure it's not the same thing at all."
"But you don't know that," Azula insists. "And if it is the same thing, it's because of me. There's no other answer."
"Azula, this is not your fault, okay?" Ty Lee assures her. "We have a beautiful daughter. She's smart, she's very sweet, and what if she did have what you have? Look at you. Look how you turned out."
"After an adolescence of pain and misery," Azula mutters.
Ty Lee pulls back and brushes Azula's hair behind her ear. "But that was mostly because of you father, right? And all that pressure that was on you? And there's nothing like that in Shinzei's life." Ty Lee offers her a smile. "You made sure of that." She leans toward Azula again and brushes her lips against her cheek.
"She'll be okay," Azula replies firmly, more for her own assurance than Ty Lee's.
"I hope so." Ty Lee shrugs. "Maybe it was just a one-time thing. Maybe it won't ever happen again."
The next time is five months later, at a pyrotechnic display on the beach on Ember Island.