Death Stranding has many trophies and achievements that you can collect, one of which is Snooze ‘n’ Soothe, which requires you to Heal by Sleeping.
In order to trigger this you need to at least start Chapter 3, here you will get BB and the ability to sleep (though the latter part may not actually be a requirement and thus you may be able to sleep from an even earlier Chapter)
This is very similar to the A Baby Blessing trophy / achievement. In order to get this trophy / achievement you need to go idle, thus go and get a nice cup of tea or something.
Eventually, Sam will get impatient of waiting and either start whistling or sit down, we are hoping he decides to sit down here. If he does not, then just nudge him and try again. Thus, this can be somewhat of a grind in order to get the correct cinematic.
Once he does finally decide to sit down, you can then choose the option to sleep and thus the trophy / achievement should then pop!
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