guitar to bass

So I was wondering if any of you could help me out. My dad won't let me get a bass guitar until I learn the "regular" guitar. But frankly I suck at it, for some reason bass seems better for me. My dad doesn't seem to understand this though. Do any of you have any suggestions on how to get him to understand what I'm trying to tell him? Does being able to play the "regular" guitar make a difference in learning the bass guitar? I'm seriously confused on what he's trying to teach me with this. Does it even make sense to you guys? If you could would you mind explaining to me?