Not very hard, has the same chordsequence almost the entire song except for the intro and first verse.
Chords in song:
Dm F C Bb A
[Intro]
Dm (Dm) F C
[Verse]
Bb Dm F C
I don't know if we should be alone together, I still got a crush, that's obvi-
Bb Dm F C
-ous, If nobody's around, what's stopping us?
Bb Dm F C
Everywhere I Go you show, whatever, I don't ever mind sharing oxy-
Bb Dm F C
-gen, I just wanna get lost in your lungs
[Pre-Hook 1]
Dm F C Bb
Just a baby, but she's growing up so fast
Dm F C Bb
And I'm allergic to the waiting
Dm F C Bb
She's just a baby girl, And I love to watch her dance
Dm F C
But it's making me Go crazy
[Hook]
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Dm F C Bb
(Can you let your baby be my girl?) x4
[Verse 2]
Dm F C Bb
I don't think that we should be around each other, When you're in the room, you get my-
Dm F C Bb
-eyes, You open your mouth, I'm hypnotized
Dm F C Bb
I can make you laugh until you cry
Dm F C Bb
You know that you got all mine, You know that you got all my att-
Dm F C Bb
-ention, You know that you got all mine
[Pre-Hook 2]
Dm F C Bb
Baby, I can't help but call her that
Dm F C Bb
Even though I shouldn't say it
Dm F C Bb
She was my baby girl, I might never get her back
Dm F C Bb
But I don't mind being patient, yeah
[Hook]
Dm F C Bb
Can you let your baby be my girl? x4
[Bridge]
F C Bb Bb Bb
F C Bb Bb Bb
F C Bb Bb Bb
F C Bb Bb Bb A
Dm F C Bb
Okay, I'm just gonna tell you what I...
Dm F C
...gotta say, right here
Dm F C Bb
I'm sorry Dave, I never meant to hurt your baby...
Dm F C Bb
...girl, She's your little baby, she's my...
Dm F C Bb
...soulmate, I don't want you to worry, she'll be...
Dm F C
...so safe right here
Dm F C Bb
Oh, oh, oh, so Dave, would you let your baby be my girl?
[Hook]
Dm F C Bb
Can you let your baby be my girl? x4
[Outro]
Bb Bb
Your baby she's mine
F C Bb Bb Bb
F C Bb Bb Bb
F C Bb Bb Bb A