Whatever works for you :)
My Son was 3 months when i started feeding him as well. He was alittle underweight for his age when i started feeding him. He could pick his head up and turn onto his stomach though. He would always look at me and my husband when we ate and would get mad so i started feeding him. He is doing perfectly fine..no problems whatsoever. I think it really doesnt matter whether they are six months or not but rather if they are ready. Every baby is different. I think its fine unless your doctor says otherwise for that baby.