Personally, I think Alf’s development has been held back by the restrictions imposed on him by his parents.
For example not being allowed to learn to climb or descend stairs until approx 3 months before he turned 2;
being restricted to a pushchair on all occasions while outside the house;
being fed only soft or puréed foods (watermelon, grated cheese, baby pouches) - this will also be a factor in his speech with muscle development being hindered;
no opportunity to develop fine or gross motor skills;
being spoon-fed by an adult even at 2 years.
The list goes on - this is just some.
It’s hard to know if there’s an underlying additional need, or if he just needs some decent adults around him.