There were two baptisms of infants named William Robins at St. Blazey 30 May 1756.

• Son of Peter Robins (wife name not given)
  
• Son of William Robins (wife name not given)
  

It appears that both stayed in St. Blazey, though no marriage for a William Robins (or Robbins) at St. Blazey ever took place at any date.

One William Robins died at Church Town (the town of St. Blazey as opposed to the parish in general) at age 58 and was buried at St. Blazey church 1 Dec 1814 [thus birth about 1756].

The other William Robins died at St. Blazey Bridge at age 73 and was buried at St. Blazey church 2 Apr 1828 [thus birth about 1755].

In the absence of any other information than the baptisms and burial records, it is impossible to tell which one was which. That is, it is impossible to tell if the William Robins who died in 1814 was the son of Peter or William -- and the same is true for the one who died in 1828.