Whether venial sin can be in anyone with original sin alone?

❌ Objection 1 : It would seem that venial sin can be in a man with original sin alone. For disposition precedes habit. Now venial sin is a disposition to mortal sin, as stated above (Question [88], Article [3]). Therefore in an unbeliever, in whom original sin is not remitted, venial sin exists before mortal sin: and so sometimes unbelievers have venial together with original sin, and without mortal sins.

❌ Objection 2 : Further, venial sin has less in common, and less connection with mortal sin, than one mortal sin has with another. But an unbeliever in the state of original sin, can commit one mortal sin without committing another. Therefore he can also commit a venial sin without committing a mortal sin.

❌ Objection 3 : Further, it is possible to fix the time at which a child is first able to commit an actual sin: and when the child comes to that time, it can stay a short time at least, without committing a mortal sin, because this happens in the worst criminals. Now it is possible for the child to sin venially during that space of time, however short it may be. Therefore venial sin can be in anyone with original sin alone and without mortal sin.