Here's another 4 chord song to teach your student or child.
I teach the right hand chords on the first line and help them identify the kind of chords they are, ie. G 2nd inversion, D root position, e minor 2nd position, C root position. Have them play the chords several times, then you play the left hand with them.
Next, have them play the left hand. On the second measure they will need to move their 3rd finger to the E.
Duet the first line with student playing left hand and teacher/adult playing the right hand. This makes it so much easier to play before they put hands together, which is the next step.
Teach lines 2 and 3 with learning the left hand chords first. Then follow the same procedure of dueting it, they play right hand, duet, they play both hands.
The last two lines can be taught, notating that on measure 3 the right hand needs to move the 2nd finger to the B.