@shadowlioncub thinks your drawing is amazing and thinks no human alive could draw that good XD He was unsure how to react when I informed him that I was reasonably sure you were a human XD They do look so cute sitting together like that :)
I'm going to guess that the sister's name is never mentioned (it's been A Very Long TimeTM since I read the books) as she had a bunch of different names across different media/retellings.
@shadowlioncub is very adorbs omg * ___ * will he accept if a spider draws them instead? :O
(please thank @shadowlioncub for me, he makes a spider very humbled and very happy <3)
aaaah, poor sister did not deserve a name~ but that is fine, the story is alice's after all :>
He said he will accept a spider drawing that, and "that is one VERY talented spider!" XD and he's glad he made you happy :)