My son is 2.5 yrs old. He recently sings the following song:
1 Little, 2 Little, 3 Little Indian,
4 Little, 5 Little, 6 Little Indian,
7 Little, 8 Little, 9 Little Indian,
10 Little Indian Boys.
A very common song, right?! But he will sing all the numbers in Cantonese and all the rest in English, sure with the "s" sound after the "boy". If we deliberately omit the "s" sound, he will say "It is not boy, it is "boys". Very funny
I have tried to sing his song, it is very difficult. But he can sing fluently.