By 6 month if the birth weight is double then it’s really good growth

<a style="text-decoration:none" href="http://app.babychakra.com/article/2555"><b><font color="#3b5998">Height And Weight Chart: An Easy Tool to Monitor Your Child&rsquo;s Health</font></b></a>

Let him complete six months then you can start with solids. Check his ideal weight here <a style="text-decoration:none" href="http://app.babychakra.com/article/1101"><b><font color="#3b5998">The Ultimate Height and Weight Tracking Guide for your little Boys</font></b></a>