Sentence:  There was something not nice about triplets , though their father seemed pleased , <WSD>showing</WSD> no disappointment that they had n't been the son he wanted , saying , `` You do n't see triplets trippin ' down the pike ever ' day , Miss Jen , hon . 
Meaning of the word marked with <WSD> tags:  establish the validity of something, as by an example, explanation or experiment