Donna retreated into the TARDIS to change. Lilith and the Doctor sent the ship into the vortex.
“I don’t know how I stood wearing one of these every day,” Lilith said, looking down at her dress. “I need to get into some jeans.”
“Don’t you think it was a bit cruel?” the Doctor asked.
Lilith had a feeling he wasn’t talking about the dead Vespiform. No, this was about something a bit more serious. “Just forget it, Dad. You’re alive, you’ve got the same face, and everything worked out.”
“All I needed was a shock. Hell, Donna kissing me would’ve worked. But you had to go and use her instead,” the Doctor hissed. “You of all people know how I felt about her. Then you say that? For a moment, I actually hoped…” He trailed off.
“It's a shock! Look, shock! I need a shock!”
Panicking, Lilith blurted out the first thing that came to mind. “My mother is Rose Tyler!”
Lilith eyes widened. “Oh, you think, oh.” How was she supposed to go about this? He’d have to forget anyway. “I wasn’t just using her name as a shock tactic,” she said, gently. “Rose… Rose really is my mom.”
The Doctor looked at his daughter. “That’s impossible. She’s stuck in Pete’s World.”
“Stuck and fighting to make her way back. And she makes it. Granted, things go wrong and you decide to be a masochistic bastard and you send her away and then close the walls to the void, then I have to go get her after she changes,” Lilith rambled. “My point is, after all that, you get her back.”
“She… she comes back?” he asked, voice barely a whisper.
Lilith took her father’s hand. “She comes back,” she confirmed. “You’re song isn’t over, Dad, not yet.”
The Doctor took a moment to let that sink in. “I’m going to have a daughter with Rose.” He sank onto the jump seat.
“Four daughters, actually, and one son,” Lilith corrected. The Doctor paled. “But that’s not the point.”
He nodded, and then frowned. “What do you mean, you have to go get her? You wouldn’t be able to after I close the universal walls.”
She shifted uncomfortably. “Well…” She drew out the syllable like he had the tendency to.
“Lilith, do you know how to cross universes?”
Lilith coughed awkwardly. “I’m not saying I don’t.”
“You mean to tell me,” the Doctor said, lowly, “that there is a way for me to get Rose back, and you neglected to tell me?”
“Paradoxes!” Lilith exclaimed. “You wouldn’t want to cause a paradox, would you? Besides, it takes major modifications that we don’t have access to and won’t have access to for awhile.”
The Doctor seemed calmed down. “I’m going to have to forget. I can’t know she’s coming back, can I?”
Lilith shook her head. “No.”
“I have to move on thinking I’ll never see her again.”
“But in the back of your mind, you’ll know.” She sat next to him and laid her head on his shoulder.
“I miss her,” the Doctor said, hoarsely.
“I know, Daddy,” Lilith whispered. “I do too.”