Me and DS have a bit of a sing song after stories when he is tucked up in bed (he is 2.9). We always always have to start with twinkle twinkle and baa baa black sheep but now I need some inspiration past nursery rhymes!
Songs I like to sing:
morningtown (train whistle blowing, makes a sleepy noise, ...)
my grandfather's clock (lovely rhythym, love the line 'it was bought on the morn of the day that he was born')
we went to the animal fair
victorian music hall types songs, eg My Old Man