Hi syljun
I've been doing a little research myself, into your family history, to see if I can get some clues as to what may have happened to your WTD. I can see that WTD would have only been around 5 years of age, when his dad died, in 1893. Mary Jane also had another baby, not long before her first husband died. I can also see that WTD isn't living with his mother, her husband -Alfred-, or his siblings, in 1901. Or he could be spending the night with a relative or friend. Mary Jane also has a child with Alfred. So, the questions I am asking myself is:
Where was WTD on the 1901 census
With Mary Jane having young children at the time of her first husband's death, did she concentrate on looking after a very young baby, and the older children, and leaving WTD to go and live with a relative? Maybe there are clues in the 1901 and 1911 census
I can also see that WTD's mother was born, and spent much of her youth, in Staffordshire. Could it be that she still had relatives there, and WTD went to that part of the country?
I am fascinated to discover what happened to WTD. I will keep looking to see what I can come up with, but in the meantime, keep me posted of how your search is going.
Happy hunting, and good luck!