One of the main reasons MacCready stopped cursing was because of Duncan, of course. But I also think it was because Duncan’s first word was “fuck” and MacCready realized he needed to stop

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One of the main reasons MacCready stopped cursing was because of Duncan, of course. But I also think it was because Duncan’s first word was “fuck” and MacCready realized he needed to stop
The Sole Survivor has ADD, so when they sit and wait for several hours it's actually just them daydreaming and stimming or something while they rest. And so when the companions see this for the first time, some are like "wtf," but Nick and Piper are so understanding. MacCready's seen Duncan do that before, and Codsworth is like straight up a m o m when this happens. X6 is just like. "M'am/sir... Uh... M'am/sir..." BC he's so c o n f u s e d. Dogmeat sits in their lap though
Headcanon that Duncan gets better eventually and Daisy’s contacts get him to the commonwealth. He gets to be with his dad, and makes really good friends with Synth Shaun.
MacCready loves Shaun like his own son, and wants Duncan and Shaun to meet.
Duncan had already died. MacCready went into denial after his death and refuses to believe this, so he searches all the country for a supposed ‘cure’ for his son that isn’t breathing anymore.
The reason MacCready doesn't go back to the Capital Wasteland for Duncan is because hes been gone so long, Duncan doesn't know who he is. He knows about his dad, but he doesn't remember or recognize him, and it breaks MacCready’s heart. He decides it’d be cruel to take Duncan away from the people hes been staying with, but isn't ready to face the fact that his own son doesn't recognize him, so he distracts himself with work and travelling with the Sole Survivor until he can find the strength to go back.
MacCready and Danse end up becoming close friends, and babysitting Duncan really helps Danse settle into civilian life
Both Duncan and Mac are huge fans of Steven Universe in the Present AU