He knows nothing of this little girl's mom, but he does know that baby nannies tend to be more affectionate in first class. Florence seems pleased regardless, and a happy baby is what seems to matter most.

When Jyn moves to sit down, Cassian finds himself standing up straighter again, apparently having laxed a little with his posture. "It will still be some time before I can make it back to Mexico proper, Miss."

He wants to ask her where she's going - America, obviously, but where else? Why is her family traveling from England? There's more he could say about Mexico too and he finds he wants to, but Rules and Regulations cut him off.