This is mostly a copy-paste from the older acoustic version, so credit goes to user edcarroll24.
The only changes are the lyrics which are brought from the newer Live in London recording.


In places where Father and Son sing at the same time the parts have been written directly together with the
chord to be played above both. Like so...

              
[Son]  Just a 

            
guy and his li

ttle guy
[Dad]  Just a guy and his little guy


[Chords]
   x02210
  x02010
 302210
    x32010
  x20010
    xx0232
    320033




[Verse 1]
       
[Son]  Hey dad
       
[Dad]  Yes son

?
              
[Son]  I thoug

              
ht today was a

 
 lot of fun
       
[Dad]  Hey son
       
[Son]  Yes dad

?
            
[Dad]  Today w

              
as the funnest

       
 day a dad eve

r had


[Bridge]
             
[Son]  Buildin

           
g castles in t

  
he sand
            
[Dad]  Just yo

/
u and I
             
[Son]  Driving

           
 round in the 


car
              
[Dad]  I even 


let you drive
             
[Son]  Eating 

           
dinner from a 


can
            
[Dad]  Dads yu

/         
mmy can deligh

t
              
[Son]  Just a 

             
guy and his li

          
ttle guy
[Dad]  Just a guy and his little guy


[Verse 2]
       
[Dad]  Son I k

now it's hard 

to watch your 

daddy cry
              
[Dad]  It hasn

              
't been easy s

          
ince your mama

 died
       
[Dad]  But don

't you worry, 

we'll be alrig

ht
            
[Dad]  Remembe

              
r we're a fami

         
ly just you an

d I

           
[Son]  You kno

w very well, d

ad, mama didn'

t die
              
[Son]  She jus

              
t hooked up wi

    
th another guy
       
[Son]  His nam

es Trevor and 

now they live 

together
            
[Son]  That's 

              
where you pick

          
 me up on Frid

ay nights


[Bridge]
             
[Son]  Dont yo

           
u wonder where

   
 I go?
              
[Dad]  You alw

    
ays go for a w

hile
             
[Son]  You nev

           
er ask me wher

       
e I've been
              
[Dad]  Don't w

       
ant to cramp y

our style
             
[Son]  When I 

           
see you on wee

 
kends
              
[Dad]  You alw

    
ays make me sm

ile
             
[Son]  That's 

              
the smile of y

               
our little guy
[Dad]  That's the smile of my little guy

[Verse 3]
       
[Son]  Hey dad

 can I sit on 

your knee?
              
[Son]  Got que

              
stions about t

              
he world that 

    
are troubling 

me
       
[Dad]  Tell me

 every questio

n that you hav

e for me
            
[Dad]  And tel

              
l me does your

            
 mama still me

ntion me?

          

              
[Son]  When I 

             
grow up what w

      
ill I do?
              
[Son]  Will I 

         
be a fireman o

          
r work in the 


Zoo?
              
[Dad]  You can

             
 do anything t

        
hat you choose
           
[Dad]  The wor

            
ld is at the f

          
eet of a kid l

      
ike you
              
[Son]  Just a 

            
boy and his da

d
              
[Dad]  Just a 

            
dad and his ki

d
              
[Son]  Hanging

     
 out together
[Dad]              together

[Verse 4]
             
[Son]  I'd lik

              
e to live on t

   
he moon
              
[Son]  Or mayb

            
e live on a st

ar
           
[Son]  Or will

          
 I be like you

/        
 dad and live 

in the car?
              
[Dad]  You can

             
't live on a s

              
tar you'll dis

          
integrate to a

sh
              
[Dad]  And whe

           
re you spend y

            
our nights is 

       
dependent on c

ash
              
[Son]  Will I 

             
fall in love a

              
nd will it be 


forever
           
[Son]  Or will

              
 she leave me 

          
one day for so

/         
meone like Tre

vor?
              
[Dad]  Well, y

              
ou just never 

             
know how love 

     
will end
              
[Dad]  But nev

           
er ever introd

            
uce her to you

         
r handsomest f

riend
              
[Both] Just a 

            
boy and his da

d
              
[Both] Just a 

            
dad and his Ki

d
              
[Son]  Hanging

     
 out together
[Dad]              together


[Chorus 1]
       
[Dad]  Since y

our mama ran a

way
              
[Dad]  I've be

 
en thinking ab

out your lonel

y little heart

 every day
           
[Dad]  But you

, you don't ne

ed to feel so 

sad
              
[Dad]  You've 


still got your

 dad


[Chorus 2]
       
[Dad]  Since y

our Mumma ran 

away
       
[Son]  No, she

 didn't run aw

ay
            
[Dad]  Been th


inking about y

our lonely lit

tle heart ever

y day
       
[Son]  Dad, sh

e's living in 

our old place
             
[Dad]  The two

              
 of us, we don

              
't need to fee

     
l so sad
       
[Son]  I'm not sad
              
[Son]  Because

        
  I've got dad
[Dad]  You've still got your dad
       
[Son]  And ano

ther even cool

er dad


[Chorus 3]
       
[Dad]  Ever si

nce your mama 

ran away, she 

passed away th

en ran away
              
[Son]  And man

              
, she wish she

              
 did it years 


ago
       
[Dad]  Been tr

ying to think 

of the right w

ords to say
              
[Son]  And dad

              
 she calls you

        
 an asshole
             
[Dad]  But the

              
 two of us, we

              
 don't need to

         
 feel so bad
       
[Son]  I'm not

 sad
              
[Son]  Because

        
  I've  still 

got my dad
[Dad]  Because you've still got your dad
       
[Son]  And Tre

vor bought me 

a brand new ca

r


[Chorus 3]
       
[Dad]  Love ha

s not been the

 same when she

 went away
              
[Son]  Trevor 

              
let's me watch

            
 anything I li


ke
       
[Dad]  And I'v

e been thinkin

g about my lon

ely little hea

rt every day
              
[Son]  Eat ice

              
 cream on week

        
day nights
             
[Dad]  But you

              
 know what mak

              
es me feel so 


glad
       
[Son]  I'm not

 sad
              
[Son]  Because

        
 I've still go

t dad
[Dad]  I'm still your dad
       
[Dad]  I'm sti

ll your biolog

ical dad


[Outro]
       
[Son]  Hey dad

 can I sit on 

your knee?
              
[Son]  Got que

              
stions about t

              
he world that 

    
are troubling 

me
       
[Dad]  No son 

don't you sit 

on my knee
            
[Dad]  You're 

              
too big now, y

             
ou're thirty-t

hree
              
[Dad]  You'll 

          
always be my l

      
ittle guy
             
[Son]  I'll al

           
ways be your l

      
ittle guy
              
[Son]  But I'm

           
 thirty-three
[Dad]  But you're thirty-three