Foot + Toot + L = Flootoot

The question was:
Andrew and Alice (brother and sister) come from a large family. Andrew has as many brothers as he has sisters, but Alice has only half as many sisters as she has brothers. Is this possible? If so, how many brothers and sisters total are in the family? If not, draw a picture of a donkey.

And Here's the answer
4 brothers and 3 sisters

One way to solve this question is with algebra...
b = total brothers, s = total sisters.
For Andrew: b-1 = s
For Alice: (s-1) = b/2
when you solve that you get b = 4, s = 3.

Sadly, noone drew a picture of a donkey for us.