Visiting his in-laws is always both exceedingly strange and excruciatingly boring for Sasuke. He isn't sure why he endures it.
No, he knows. Because this is the wife his brother chose, because this is the baby girl he fathered.
Because Uchiha Tamaki is née Nekoka Tamaki -- cat-lover opportunists who never bothered to take a side because they were going their own way -- and shows it in everything she does, every stray she brings back home just because and every stray she lets go, every potted plant she adds to the jungle of their house (she is Not Uchiha) but Taimi has the black eyes Itachi is now missing.
Sasuke visits like clockwork, once a week. He and his brother never have anything much to say to one another (or too much, with the same result,) so usually they just sit in his office and read the newspapers. Sometimes as Itachi's pen scratches words on paper Sasuke pretends to look at the books lining the walls, at least those whose titles he can see without having to move enthusiastically-leafed plants off their perchs. Tamaki walks by and watches them like she's not sure why they bother but doesn't try to break in between the two of them. Good, because that silence, she has no place in it. It's theirs, Itachi and Sasuke's.
Doesn't stop it being awkward, and long, and boring.
Doesn't stop Sasuke from falling asleep like clockwork, in Itachi's office, buried under a dozen cats.
Every week he wakes with little Taimi patting his leg or his arm or whatever part of him she can reach with her tiny hands and short round legs, and Itachi's eyes -- green behind his reading glasses -- are politely averted, but smiling anyway, and he pretends he has something to do elsewhere so that Sasuke can pretend no one knows he lets his niece climb in to share his lap with the cats, so they can nap until dinner.