DD is 3 1/2 years and has kinda outgrow this trike:

It was a pass down from a friend and she really likes it. She got some bruise on her lower back from the raised seat, I guess she's getting a bit too tall for the trike that her lower back keeps rubbing/hitting the seat when she pedaled. Anyway, we're thinking of getting her a bike that she can at least use for several years. I'd imagine she will need training wheels to begin with and can take off the training wheels when she doesn't need it anymore.
She's 34.5 lbs and height is about 38 1/2 inches.

I've no clue what kind of bike we should get her. Any recommendation will be appreciated. TIA.