4 month old JR girl just wont?

by cheryl
(canada)

ok so my baby girl jersey is only 4 months old..i have 2 questions..she is finally potty trained and goes to the door when needed out..now she has been going on her own for awhile then recently will not go outside without me..why is this? and my second question is she is brave enuf to run up and down the stairs with no issue but she will not jump up on the couch.she just stands there wining till i pick her up..shes not a shortie but also isn't a long legged..kinda in the middle..i know that if she actually got a run at it she could do it..but she wont.