If I were a superhero and had any power in the world
I would have...
Super Speed, anything you need I could be there in a FLASH!
No second thought...no maybe or not, I would be there super fast.

Though, that's too obvious.

No, I would pick...
Super Hearing, that would be my choice, I would tune it ONLY to your voice
and know the moment you were in distress. That would be good I guess...

No, not that either.

I would pick...
Super Flight, so that every night I could take you to the stars (though the air might be tight)
it would be super right.

No.
I would pick...
Super Linguist, so I can speak every word, noun and verb into your ear in a feeble attempt to dry up each tear.

No, I would pick time travel  and go to the moment you were first sad.
I would have super vision to see you on the days you are glad.
Telepathy to know how you feel.
Super strength to move ANY mountain... when you need healed.  

Forgive me for this, it may be a bit extreme.
What you need is not a superhero by anyway shape or means ...what you need is a hug.

Yes, that's it!
If I were a superhero and had any power in the world...it would be Super Hug.
I would hug you so tight till all doubt has left your mind every night.
I would hold you in my arms till you knew your worth.
No, I can't save the Earth with a hug, I can't change everyone's life with my embrace.

But just in case ...I will start with you, I will hug you regardless.
In my arms your petite body will be cocooned till the sun turns in to the moon.
I will hold your neck while you head rests on my chest.
I will put in CHECK... every thought, pain and neglect with the only power, enchantment and medicine that I posses...
My hug.