Body composition is more important than weight, IMO. A person with more muscles will look thinner but weight more. You should get a fat/muscle ratio test to determine what that should be and not worry so much about weight. I weigh more than I did in college but I am two sizes less. It is the weight training for me that makes the difference.

It depends on her body type:

1. Ectomorph
   Thin and frail. She has a tough time putting on weight, has low body fat and typically a fast metabolism. Think linear or ruler body shape, narrow shoulders, waist and hips. Celebrity ectomorphs? I’d go with Kate Moss, Kiera Knightley or Cameron Diaz.

2. Mesomorph
   The athlete. Strong structure, your hips and shoulders are usually the same width which makes you very symmetrical, like an X. Usually you can be hourglass, pear or apple shaped. You can gain fat more easily than the ectomorph, but with the right cardio balance, you can maintain a lean muscle body. Think Gabrielle Reese and Jennifer Garner.

3.Endomorph
If you´re an endomorph, you already know you have a hard time losing body fat and you gain weight easily. You are usually curvy, have a softer and rounder body and have a slow metabolism. Jennifer Hudson, Oprah or Marilyn Monroe are three celebrity examples.

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I dig the hourglass form so as long as that is there weight is not as important in my opinion.

I'm 5'3 and have always been told it's around 125. Hold on while I laugh. .........................................................................................................
You do you. Don't let people give you their ideal body size. If you are healthy and happy, who cares?