Secondly, they aren't white.. While some double merle dogs are almost pure white, they can go the complete range all the way up to a dog that you would think is a just a normal merle (most fall somewhere in the middle).
In between five and six months, your baby usually starts to sit up with your help, holding his head in an upright position, keeping the back straight. He may even be able to sit for a second or so without taking any assistance from you, before toppling down after a while [1] .
Report Abuse. My son is 9 months old and he started when he was 6 months old. Every child is different but I think 6 months is the average age for sitting up. Once my son sat up he was crawling and pulling himself up before I knew it. Time goes by so fast!