Given the cryptic nature of your non-reply, my brilliant point stands uncontested. As a Christian, Michael Phelps should have married the girl as soon as she got pregnant.
Quit “shoulding” on Michael Phelps, or anyone else for that matter. Self-righteous attitudes such as yours do not draw people to Christ; they turn people away.
I understand why he did not rush to marry her at this time, and wish them every blessing in achieving a solid marriage going forward. A rigid, shame-based worldview dims understanding and the light of Christ.