Growth Stunted RTB: Will she ever catch up?

Hello everyone,

So I was planning on getting a coastal carpet python to add to my collection, but ended up rescuing another RTB that is very small for its age.

Her prior owner was a lady who housed her in a 3x2ft enclosure with a Corn Snake. I guess she was unaware that they got large and thought they stayed the size of a Corn, and wanted to give this girl up once she figured that out. She fed the RTB 1 mouse once a month.

So basically, she is 3 years old according to the lady and is only about 3 feet long, and her girth is only about 1 inch(diameter). My male RTB is younger, longer, and thicker than her at 1.5 years. I've been offering her one fuzzy every 5 days until she bulks up, and then will offer once per week. (If that is wrong, please let me know, I don't normally deal with emaciated snakes)

My question is, will she always be smaller than the norm? Or will she eventually catch up to the proper length with proper feedings?