This is the census document from 1901. It shows Peter living with his wife Mary and their six children: Mick, Mary, Peter, Patrick, Bridget and Joseph
All of the family can speak Irish and English and all of them can read and write except for the father
The 1911 census shows only four people left in the family home: Peter, his daughter Mary, his son Patrick and his daughter Bridget
Peter is given as a "Widower" while the other three are given as "Single"
If the form has been filled out correctly, then Patrick (who is 26) is no longer able to speak Irish.