Pushing their trolley down an aisle in Tesco, the Doctor and Rose were engaged in a heated debate.

Rose glared at him. "Well, which one do you want?"

"I don't care!"

"You obviously do, or you wouldn't be sulking!"

"This is disgustingly domestic," he grumbled. "Just pick one."

"Fine! Then I pick this one."

He held up a different one. "But this one makes our clothes smell nicer."

Rose gritted her teeth. "Then let's go with that one! Jesus, you could've just said that."

The Doctor narrowed his eyes at her. Rose folded her arms. They stared at one another for a few moments, and then the Doctor carefully, slowly put the detergent he favoured into the trolley. They resumed walking down the shopping aisle in silence.

Absent-mindedly, the Doctor reached onto a shelf as they passed a particular product, dropping a pack of their usual condoms into the trolley. They never had any arguments about choice in that regard; they knew what they liked. Which was why the Doctor was astounded when Rose calmly and casually retrieved the condoms from the trolley and put them back on the shelf.

"Don't tell me you're gonna argue about that, too," he said, halting their progress by stopping short in the middle of the aisle.

"What?" she asked, a picture of innocence, trying to distract him by stepping in between him and the trolley and taking over the pushing, guiding them into the next aisle.

"Rose…?"

"Yeah?" she replied, as she tossed a few shampoo bottles into the trolley.

He studied her warily. "Are you planning on withholding sex just because I wanted a different laundry detergent?"

She snorted. "Course not. God, you do come out with the strangest things sometimes. We're not in some crappy '90s sitcom, you know."

"It's just, I can't help but notice that you put a certain item back on the shelf."

Rose just shrugged, looking strangely shy. The Doctor stood in front of the trolley, stopping her from going any further. "Rose, are you trying to tell me something?" he asked, his heart beating a little bit faster.

Her expression softened, no doubt noticing the glimmer of hope in his eyes. "Oh. No, I'm not…I'm not pregnant, if that's what you're thinking."

He tried not to let his shoulders slump, knowing that would be a dead giveaway. He swallowed, then replied carefully, "Okay. Then?"

Stepping around the trolley, Rose smiled at him and looped her arms around his neck. "Just thought, maybe we could, I dunno. Start trying?"

The Doctor's eyes widened and he wrapped his arms around her waist. "What, really?"

"Yeah. I've been thinking for a while, now…I'm ready."

He looked a little uneasy, and Rose's heart sank.

"What is it?" she asked. "I thought you wanted…"

"I do," he assured her, stroking her back soothingly. "I really do. It's just…"

"What?"

He tilted his head to the side. "Rose, we just argued about something utterly ridiculous; do you think we're mature enough to bring actual physical human beings into the world?"

She laughed. "Oh, come on. Everyone argues, Doctor. Everyone."

"Yeah?"

"Yes. It's nothing to get all weird about." She stood on tiptoes and kissed his cheek. "Now, do you want to be the father of my baby or what?"

The Doctor smiled slowly, tightening his grip around her waist. "Oh, completely."

"Then let's finish up here and get home," she said, giving him a saucy wink.

He nodded quickly. "Good idea." He hastily grabbed the trolley and pushed it down the aisle.

Rose laughed. "Doctor, wait up, we have a list, you know. We haven't even got any food, yet!"

Slowing down, the Doctor looked back at her sheepishly. "Right. I knew that."

He reversed back to her, donking one of the wheels against his foot. As he winced, Rose patted his arm, making appropriate consoling noises. Then -

"Race you to the frozen aisle!" she suddenly grinned, making a run for it as the Doctor fought with the wonky wheel on the trolley.

"Cheater," he mumbled to himself, his lips twitching. Then, thoughtful, he squinted at her dashing away, realising he could beat her if he went in the opposite direction and down the pet food aisle instead.