I've had a quick look at your tree on Ancestry, and I think I see the problem, assuming the birth certificate you're referring to is for Henry Horsfield, born 1882 in Ashton under Lyne?
If this assumption is correct, the birth certificate you've attached to his birth event is the actual full certificate - there is no other information available formerly recorded. It indicates that Henry Horsfield was born illegitimately to Sarah Ann Horsfield, and after a little more research it can be determined that Sarah Ann was unmarried at the time. I'm sorry if this is a shock, but it was very common in the days before birth control.
The newspaper obituary for Henry is a bit misleading in that it implies his mother Sarah Ann was "Mrs" Horsfield and that her maiden name was Watkins. This is compounded by Sarah Ann's obituary saying that she was the daughter of Stephen and Maria Watkins. In actual fact, it would appear that Sarah Ann was herself the illegitimate daughter of Maria Hors(e)field, who later (much later in fact, in 1882) married Stephen Watkin.
The 7 year old Sarah Ann Horsefield, her mother Maria Horsefield, and her grandparents James & Mary Horsefield were living together in Ashton under Lyne in the 1871 census. If you search for Maria Horsefield in this census, and click on the one who was born 1843 in Ashton under Lyme, you'll see the family.
I hope that helps - it's a bit confusing and a little different from the way you've been led to understand events by the obituaries, but I believe it to be correct. :-)
Christine