Well of course Gavroche wouldn't have missed a beat. Not only in the technology, which they would start showing him soon. With the rest of the world. With how people had changed. How they interacted with each other. And with his sister and the student they'd both followed so willingly. The boy was smart, too smart for his own good at times. And so help him, Enjolras loved him. They all had, every one of them. He was the face of what they fought for.
But he couldn't help the shy smile that slipped on to his face when Gavroche's last sentence came out. He was absolutely right. Enjolras did smile at his sister. And often. Mostly because he loved getting her smiles in return. He smiled at her over the dinner table, and when he returned to the Inn from work, and when he rolled over in the mornings and she was the first thing he saw. Smiling was certainly easier with her around.
"We've both been here a long time," Enjolras admitted, his cheeks flushing pink. "And I believe, without either of us noticing it...well, we fell in love." The last part was spoken into his lap as he avoided the boy's eyes. Shy was not a word anyone would use to describe the extroverted, outspoken leader of the Revolution. And yet, at that moment, he closely resembled a schoolboy, asking for a first dance. When he looked back up, his face was filled with determination, but his expression was honest and open. "What I'm saying is, I love your sister. She's my world. There is little I wouldn't do for her." He shifted on the bed to face Gavroche more fully. "Ordinarily, I would ask this of your parents. But they're not here and even if they were, I feel they'd spit in my face for being so brazen. So instead, I'll come to you, as the only other person who could possibly love her as I do." The child didn't realize that he'd already proposed. That could be explained soon. But without his blessing, it would certainly put a damper on their plans, so best to do so. "I would like to take Eponine as my wife. Which would, of course, make us brothers. But only with your consent, my friend."
Because, frankly, it never hurt to address the younger man as an adult. And in so, so many ways, he truly was.