Great story NY, wonderful when information is passed down through the generations, it gives incite into who our ancestors were.
Going back over the thread, I was intent on research and missed a few of your thoughts and questions. If you google the 'name Mary - Maria'. Mary is given as the English version of Maria or Miriam originating from the bible and the virgin Mary.
I do not know if it was interchangable in Wales around that time, but her mother was Mary, so perhaps Maria's name was written as the English version by others sometimes?
As for Williams work...the main occ around that time in Merthyr was Iron if you google there is quite a lot of information. Others were of course coal mining.
It was not uncommon for children to be brought up by grandparents when the mother died, it seems that Maria may have died in childbirth with her youngest daughter, and namesake possibly. It would be very difficult for the father to work and care for such small children as you mentioned.
The only likely possible for Will in 1841 I can find is possibly living/lodging with John James 25, wife Mary 25 and 2 children under a year old. Although it could be he is on his own...sometimes the strokes enumerators give to end household can be misleading. Ages in the 1841 were nearly always rounded down to the nearest 5 if over 15. So ages are approx.
1841 - H0107 piece 1415 book 6
Address Patient Street ?? Merthyr Tydfil
Wm Rees, 40, coalminer, born in county
Just for info there is also an ancestral file submitted on the IGI for John Rees and Mary Jones 11 children are listed
Cas
