In Reformed soteriology, there are some clearcut groups of people. The primary distinction is between elect and reprobate. That's fixed.
An overlapping distinction is between regenerate and unregenerate. It's overlapping because election and regeneration go back to God's timeless choice, whereas regeneration occurs in time. The elect can be regenerated at different stages of life. Unlike election and reprobation, regeneration is fluid in that respect.
There are other related, generally clearcut distinctions. You have a group of people who live and die outside the pale of the Gospel. You have another group who are devoted to atheism. Likewise, you have a group who consciously repudiate the Christian faith.
There is, though, an in-between group, or type of group. For instance:
Since Christian faith is primarily trust rather than intellectual mastery, even a young child can give a credible profession. In judging what is credible leaders must take into account the capacities of the one who is expressing faith.
For very young children, the children’s response to their parents is the primary avenue for expressing their relation to God. Parents represent God to their children, by virtue of their authority, their responsibilities, and their role as a channel for God’s blessings. Children first learn what God is like primarily through their parents’ love and discipline. The Fatherhood of God is represented through a good human father. God’s forgiveness of sins is represented primarily through the parents’ forgiveness and patience towards their children.
Although Poythress is referring to young children, the principle raises questions about analogous situations. If a parent, especially a Christian parent, can be a temporary stand-in for God or Christ, and if trusting a parent is implicit faith or vicarious faith, then can some adults, who are not professing Christians, be saved indirectly because a Christian friend or family member subliminally represents Christ to them and for them?
They are the closest that some people come to Jesus. Insofar as that they love, trust, and admire their Christian friend or family member, and do so in part for his Christian virtues and graces, are they believing in Jesus via a Christian representative? Does he stand for Christ in their affections, even if they don't consciously make that connection?
There are certain passages where believing in or acting on behalf of a Christian representative is equivalent to believing in or acting for Jesus:
The King will reply, "Truly I tell you, whatever you did for one of the least of these brothers and sisters of mine, you did for me" (Mt 25:40).
The one who hears you hears me, and the one who rejects you rejects me, and the one who rejects me rejects him who sent me (Lk 10:16).
Truly, truly, I say to you, whoever receives the one I send receives me, and whoever receives me receives the one who sent me (Jn 13:20).
Unlike inclusivism, which cuts the nerve of evangelism, this still depends on a Christian witness and Christian presence.
Some people, due to social conditioning, have a tremendous impediment to Christian faith. An impediment they never entirely overcome. Are there situations where a Christian friend or relative forms the bridge? What I've discussed is too speculative to furnish a firm answer. It may be enough to give reason for hope, but not enough for confidence.