"Bienvenidos! Estan en su casa."
I have hypothetical conversations in my head all the time, and the other day I was lunching alone, looking at the welcome hanging above the breakfast room doorway. I thought about explaining "bienvenido" to Walker.
It breaks down to "bien" and "venir" -- literally meaning, come well. I hope that when you come here, you come well. I hope that you are well when you come into my home and I hope that your stay in my home goes well, makes you feel well, and that all in all, all is well.
And then I realized it's the same in English. Welcome.