" for all have sinned, and come short of the glory of God; "( Romans 3:23 ). <------That includes infants.
All have sinned and fallen short of God's righteous standards. Yes.
" For [there is] not a just man upon earth, that doeth good, and sinneth not." ( Ecclesiastes 7:20 ).
" Do ye indeed speak righteousness, O congregation? do ye judge uprightly, O ye sons of men?
2 Yea, in heart ye work wickedness; ye weigh the violence of your hands in the earth.
3 The wicked are estranged from the womb: they go astray as soon as they be born, speaking lies." ( Psalms 58:1-3 ). <--- Here the Lord gives us a glimpse of what mankind is really like, in our hearts and immediately following our birth.
Seem harsh?
Remember Dave, this is God speaking, not men.
The natural path of our sinful nature. Obviously, a point is being made here. Babies don't speak coming straight out of the womb. That would be funny though: "Dang, what the..." "It's cold out here!"

If you hold to reading these passages literally without regard for the context or the point being made, then you must also conclude that Ecclesiastes 7:20 above only applies to men, not to women, children, or infants.