Firstly, no one said or believes that you are not a child of God if you are not baptised. Even the heathen are children of God -- even Canaanites as they were created by Him.
Your salvation is from Christ, the same Christ who said He who believes and is baptized will be saved. (Mk 16:16) , the same who said [U]nless you repent you will all likewise perish. (Lk 13:3), the same who said ,b>[H]e who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. (Jn 6:54) and he that shall endure unto the end, the same shall be saved. Matt 24:13
It's not just saying "Lord, Lord", it's not just belief.
"Baptistm now saves.." through God's grace, through the one-time sacrifice of Jesus Christ, the same One who gave us the above commandments. Baptism plays a role in the salvic process as commanded by Christ. For infants who do not receive this, I personally believe that God takes care of the little ones, and the Church holds that God is merciful -- He never commanded for all exceptions, He commanded what we, the ones who grow to reason ought to do in our salvic process.
So you are at odds then with the Catholic originator of this thread who puts fear into your crowd by suggesting there are dire consequences for your child if he/she dies without baptism...
So much for your beleaguered Catholic unity...