Talk to Pediatrician on RLS, Poor Weight Gain

A.o.A doctor, My daughter was born premature at 32.5 wks with 1200g weight. Now that she's 3 years old, her weight is 10-11kgs which concerns me alot. I have visited many peadiatricians but they say it's normal acc to her birth weight. Secondly, she has developed RLS since she was 4 months. It happens mostly at night but she sleeps after 5-10 minutes of moving her right leg vigorously. I feel that this is affecting her walking as well. Plz guide.