Hello my son is 15 months 7 days old, my major concern is that my son is still not walking independently. He is walking with support holding sofa and chair, side walks is easy for him, but if we hold his hand allow him to walk he just walks few steps and sits down. I am giving him massage every day, but still he is taking time to walk, is it a matter of worry please suggest.I am giving him oroferxt and d3 drops too.