5 yr. old daughter w/ thyroid problem??

My name is Jessica. I am a mother of four little girls, ages 7, 6, and I have 5 year old twin girls. The twins were born premature at 37 weeks.
Both have urinary problems.
Twin A has had 3 urinary tract infections w/ ecoli being the main infection. Twin A has not had an urinary tract infection in one year.. so I think we're in the clear with her.
Twin B, on the other hand, wets the bed every other night, at least. She also has to use the restroom quickly or has accidents. She potty trained easily enough at 2 yrs old. She is in the 90th percentile of her weight ratio. Her eyes look very big. She is very, very emotional. She screams, throws fits, cries at the drop of a dime, gets her feelings hurt very easliy by grown ups.. not so much by her peers. She eats just as much as her sister does, but carries her weight differently. Twin A is very petite and soft. Twin B is the opposite, very bulky and solid.
I, the mother, have had a thyroid problem since I was 7. Started with hyper, then had radio active surgery at age 12.. and am now hypo.
Twin B has no goiter visible. She takes a multi-vitamin, extra vitamin C, and vitamin D3 everyday. She gets into trouble at school, short attention span, very playful, comes by her emotions (good or bad) very honestly/innocently. When she is not being emotional, she is very funny, and joyful. She always smiled as a baby, and even now she has a joyful personality, but seems to wear her emotions on her sleeve. Please advise on measures for emotional outbursts, short attention span, bed wetting, and weight gain.
Thank you.
Jessica