@superdoofus
If you're talking about the "Huh!? It's tiny!" line, it's really hard to tell, but it's probably Chi.
Normally you can tell what lines Chi says in the original because she doesn't use kanji, but in that particular sentence there wouldn't be any kanji in the first place.
The tone of speech does make me think Chi, but it could be either or both of them.
@15avaughn
No that's the dad there. He was looking forward to the big one.
My dad used to want to take me on all the largest roller-coasters and the like as well. I was looking forward to it considerably more than mom.
@SJ7 well there's tons of manga where we never find out about a sibling until a chapter specific to introducing them. Many manga we never even hear or see the parents of the characters even though they're supposedly around all of the time!