6 month old baby poor hand eye coordination?

My Son is 6 months old and has been doing puree baby foods for a little while. I been trying some new textures. With my first baby my daughter she was sitting up @ 5 months, could hold a baby mumum biscuit to her mouth and suck/bite, and could eat soft finger foods off her high chair tray. My son at 6 months can't sit up unisted, I put a mumum in his hand and he can't coordinate it to his mouth, tried very tiny bits of finger food on his tray and he don't pick it up, tried a piece in his mouth and he just lets it fall back out. It's almost like he doesn't know how to chew/gum. is this normal?