Hi Michelle
Welcome to rootschat.
Looking at the 1861 census you will see that there is another son, John, born 1855 and also that the place of birth for Thomas and the children is given as Ancroft.
Go to 1841 census for Ancroft and you will find Thomas Young age 23 still living with parents and siblings. His parents names are William and Isabella which fits nicely with the names of his children.
Can you confirm that his wife's maiden name was Grey?
Christine