Spirithound and twb1621,
Although I agree with you both on points #1 and #2, I disagree, in a certain respect on point #3.
An adult may receive the sacrament of Baptism validly, but not completely efficaciously. If they do not have sorrow or attrition for all of their serious sins, then they place an obstacle against two of the effects of baptism: forgiveness of sin and sanctifying grace. They do receive the effect of a permanent character, however.
They would, in that case, need to have sorrow for their sins sometime later, and receiving forgiveness either through sacramental absolution in Confession, or through Anointing of the Sick, or through some other extra-sacramental means.
So, in respect to #3, it seems it is possible that an adult may receive a valid baptism, then die, but not go to heaven.
What do you think?
VC