She had seen them at the bistro. The way they whispered to each other, standing too close for comfort for her liking. He was engaged to her sister, yet it seemed he was interested in Bethany Platt.

Sabine was two years younger than Sinead, but she was protective of her after all she had been through. Sabine was the first to volunteer to help out with Bertie, sleeping on the couch in their living room some nights so they both got a decent night's sleep.

Sinead was overwhelmed with work and Daniel was at the bistro with Bertie. Sabine sighed as she carried the grocery bags, finding Daniel and Bethany sitting with Bertie.

She pursed her lips, forcing a smile on them when they looked at her. "Busy day I see." She put the bags over the handles of the pram and reached over to take Bertie from Bethany.

"Hello, baby." She cooed.

The blonde was oblivious to the way Daniel stared at her, a dazed smile on his lips until Bethany nudged him under the table. Sabine raised an eyebrow at them before deciding that she didn't want to know what was going on - yet.

She decided that she would get the answers after his shift.

"Say goodbye to daddy." Sabine leaned over so Daniel could kiss Bertie's head.

"Thank you for taking him. You're a saint, Sabine, honestly." He said, watching as she put Bertie in the pram.

Bethany stood up when customers walked in, waving goodbye to Bertie before going back to work.

Daniel moved to stand beside Sabine, smiling down at Bertie. "Don't know what we'd do without you."

"Good thing I'm sticking around then." She said, "I'll see you later."

Daniel waved as she left, biting his cheek, perplexed as his mind went back to the advice Bethany had given him. He snapped out of it and went back to work.

He came home to find Sabine rocking Bertie to sleep. He closed the door quietly, smiling when he heard her humming his son to sleep.

She could tell there was something bothering him and knew that she had fifteen minutes to get it out of him before her sister came home. Sabine took Bertie through to their bedroom, placing him in his cot before grabbing a monitor and closing the door.

"Give you much trouble tonight?" He spoke up after a few minutes, watching as she folded clothes that Sinead had left to dry that morning.

"No." She replied shortly.

Daniel was immediately confused by her change in demeanour. "What's wrong?"

Sabine finished folding a shirt, adding it to the pile before looking at him. "Are you having an affair?"

"What?"

"Are you cheating on Sinead with Bethany?" She clarified.

"Bethany? No!" He stood up from the couch, approaching the blonde. "Where did you get that idea from?"

"You're always whispering in corners together. Sinead even told me that she found it odd. She has her suspicions too. So if you're not cheating, what are you doing?" She crossed your arms and he sighed.

"We're just talking." He knew that this was it. He had to tell the truth. As scary and fulfilling as it would be.

"About?"

Daniel glanced at his feet then met her gaze. "You."

"Me?" Sabine dropped her hands to her sides in shock, raising an eyebrow at him.

"Look, it's nothing. She's a friend who gave me some advice, that's all." He said.

"Advice about me?" She asked, looking up at him when he took a step closer.

"About what I should do. Carry on as I have, or tell you how much I want to kiss you." He ended in a whisper.

Sabine stared at him. He could see from her eyes that she was processing his words. "Wait -" She moved away, standing on the other side of the couch. "You can't like me. You're engaged to my sister! Your son is in the next room!" She whisper-yelled.

"Don't you think I know that?" He sighed, running a hand through his hair. "I just...we got so close and the last thing I want to do is hurt Sinead but I can't just forget how I feel -"

"Shut up." She held a hand up. "Don't say any more."

Daniel frowned. "I know it's wrong. Sinead and I have been through a lot together, but I-"

Sabine walked to the bedroom and he grabbed her arm, turning her around. "Let go -"

Daniel kissed her passionately and her body instinctively melted into his. His kiss grew feverish when her hands went to his cheeks. He placed his hands on her hips, bringing her closer as he moved to press her back against a wall.

Suddenly, she pushed him away as she realized what they were doing, covering her mouth, shocked that she had kissed him back.

His face fell when he saw the shock and horror in her eyes. "I'm sorry - I just can't deny it anymore." He ran a hand down his face, sighing as he placed his hands on his hips.

Sabine stared at him closely. The way his hair fell over his eyes and the way he anxiously took his bottom lip between his teeth.

Daniel lifted his head when she stepped towards him. He was about to speak when the blonde placed your finger over his lips. His eyes closed partly when her thumb skimmed over his abused lip. She stared at him, uncertain of your actions as the voice in her head screaming about how wrong it was. How hurt Sinead would be.

Yet Sabine couldn't stop herself from kissing her sisters fiancée, hands on his cheeks, moving to his hair when he pulled her as close as possible.

The door opened and Sinead walked in. Sabine quickly turned away, picking up a shirt to fold. Daniel ran a hand through his hair, fixing the mess her fingers had made during their kiss.

Sinead smiled at the two of them and Sabine looked away when she kissed Daniel's cheek, not seeing the way his eyes lingered on her.

"Thank you again. You're the best sister anyone could ask for!" She hugged Sabine tightly and the blonde swallowed thickly, feeling the guilt burn her throat.

"I wouldn't go that far." She smiled weakly.

"It's true. Isn't it, Daniel?" Sinead said, going to hang her jacket up.

"Uh, yeah." He cleared his throat awkwardly.

Sabine bit your lip as she walked across the room to get her coat. "Well, I have to work in the morning. So I'll see you later." She avoided looking at him as she fled to the door.

"Wait!" Sabine closed her eyes when Sinead called to her. "Can you watch Bertie tomorrow at lunchtime for an hour or two? I'll drop him off with Daniel again." She smiled hopefully.

"Sure." She agreed before walking out, closing the door with a sigh. She pressed her back against the door, closing her eyes briefly before walking down the street.

That was close.

The next day, Sabine went to the bistro knowing that Daniel would want to talk about their kiss. Her assumption was right when he asked Bethany to watch Bertie while pulling her into the empty kitchen.

"I -"

"Yesterday -"

He chuckled softly, smiling at her. "You go first."

Sabine sighed, "Okay...yesterday was a mistake."

His face fell and she pretended not to notice as he forced a smile on his lips, nodding in agreement. "Yeah, that's what I was going to say."

"Great. So we don't have to talk about it again. You marry Sinead and we pretend it never happened." She told him. Sabine sent him a small smile before heading to the door. She had just opened it when he turned you around gently. "Daniel..."

"I love you."

He kissed her tenderly, pouring all his attraction for her into the kiss. Despite her mind telling her to walk away, Sabine couldn't resist melting into the kiss, wrapping her arms around his neck.

Somewhere along the line, she had fallen for him too. Maybe it was one of the nights she was babysitting, and he had stayed home, letting Sinead enjoy a night out with her friends. Or when she had joined him and Sinead for dinner where they really got to know each other. Or when Sinead was sick, and Sabine had held him while he fell apart.

Sabine didn't know exactly when she had fallen for her sister's fiancée, but she knew that she was in too deep to walk away.

It went on for months. His kiss helped her forget, made her lose yourself in the moment, that they were, in fact, betraying her older sister. Every caress, every kiss, every blissful whisper made her forget momentarily that she was breaking a family apart. The guilt hit her afterward, each time stronger than the last until finally the inevitable happened, she broke into tears.

Daniel was shocked since they had been sitting watching television while Bertie slept next door. He went to touch the blonde who moved away, standing up.

"I can't do this anymore!" She told him.

"What?" Daniel jumped to his feet, walking towards her. "What's wrong? What happened?"

"Us! What are we doing, Daniel?" She asked.

"Watching a movie." He gestured to the television and Sabine shook her head.

"Don't you care at all that we're hurting Sinead?" She scoffed.

"Of course I care but -" He sighed as he took her hands in his. "I don't want to lose you. Look, I'll end things with her if that will make you feel better -"

"Why? So I get to listen to her, comfort her, over the fact her fiancé broke up with her because he's sleeping with her sister! That'd be much better, yeah!" Sabine replied sarcastically.

"Well, what do you want me to do?" He asked, raising his voice.

She hushed him. "Bertie's sleeping!" She whisper-yelled.

Daniel ignored her. "What do you want me to do?" He asked.

"I don't want you to do anything! I want us to go back to how things were before we kissed!" Sabine confessed.

He scoffed. "Fine!" He grabbed his jacket and Sabine sat down on the couch, crying into her hands as he shrugged his jacket on.

"I don't want to hurt her." She admitted weakly, running a hand through her hair. "I'm such a horrible person. I don't want to hurt her."

Daniel sighed as he looked over at her. He walked over to the crying blonde, kissing her head. "I love you."

"I love you too." He sighed as he sat beside her, placing an arm around her shoulders. Sabine rested her head on his chest as he kissed her forehead.

"Is this what you really want?" He asked quietly.

"No. But it's what we need to do." Sabine lifted her head and placed a hand on his cheek, smiling softly at the tears in his eyes. "I love you. And I need you to let me go. For Sinead's sake."

Daniel looked down at his feet, exhaling deeply. "I don't want to do this."

Sabine put a hand on his arm, "It's the right thing to do." She rested her head on his shoulder briefly, leaning up to kiss his cheek. Daniel, turned her chin gently, pecking her lips.

"I'll never stop loving you. But right now isn't our time." She whispered, smiling sadly.

Daniel closed his eyes, sighing. "I love you."

"I love you too." She closed her eyes when he rested his forehead against hers.

Daniel put a hand on the nape of her neck when she kissed him, pouring all his love into the kiss. Sabine put her hands on his shoulders, stopping it from going any further.

The blonde smiled weakly as she stood up, grabbing her jacket that was draped over the kitchen counter. Daniel stood up, following her to the door.

"Goodbye, Daniel."

He could only stare as she walked out the door. Sinead would keep her in his life. Daniel wasn't sure what would be worse, not seeing Sabine every day or having to pretend that they hadn't kissed or that she was nothing more than his soon-to-be sister-in-law.

But this would make her happy, he hoped. And in the end, that's all he wanted. Even if it would be difficult for him, he would let her go.