Are you sure they are related?

It doesn't get more different than this between Ian and Sam.

SAM in the morning:

Sam:  I pick out my clothes myself.
Me:  Let's put this on.
Sam:  No, I pick it myself!!
Me:  Sam, would you like to wear this top or that one?
Sam:  No, I do it myself.
Me:  Ok, Sam whatever. Here are clothes.  Pick out what you want to wear.

Sam then proceeds to carefully consider all her options and picks something to wear.  (Now this is a good day when she has decided to take her pajamas off and get dressed in regular clothes).

I see Sam struggling and offer some assistance. 

Sam:  No, I do it myself.  GO AWAY!  (And slams the door shut after I've walked out of the room).

About 5 minutes later, Sam opens her door and proudly exclaims the following:

Sam:  Look at me!!  Sammy did it!!  I dressed myself.

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IAN, the same morning:

Me:  Ian, here are your clothes to wear today.
Ian:  Ok.