Skinner's theory.

I think the list of 50 first words does back up Skinner's theory as they are all words that the mother would say frequently to their child. For example 'shoes' 'bowl' and 'book' would all be words that are involved in the child's daily routine, which could lead to them imitating their parents by wanting to ask for a story, food, or to get dressed. This also leads to the child expanding their vocabulary which would impress their parents leading to praise, which increasing the child's confidence in wanting to try and use more words. This being Operant Conditioning  Also, words like 'no' 'yes' 'ta' are all words that are said in day to day conversations, and words especially like 'ta' or 'please' would lead to the child getting positive reinforcement meaning the parents would praise their child when they say the right words in the correct context, or by being polite by verbal or non verbal praise like saying 'well done, that's it' or by giving the child their favourite toy or a sweet. Although to dispute this, the word 'wassat' is not what a parent would say to their child, by it being a mixture of two words it shows the child's development on their own without their parents help or rewards.