That boy looks great in his Huggies diapers and he's filling his belly up so his bladder will also get full and then he will be peeing soon.
I would love to change his diaper when he gets done filling it up.
That's a perfect age for diapers and diapers are better than regular underwear anyway.
Potty training should be optional and if it were my kid I would keep him in diapers and never potty train him.