Just to confuse the issue

There is this baptism in the parish records of St Nicolas Newbury:
Date: 11th July 1779
John Pierce
Son of John and Mary Pierce
Perhaps John went to work in Highclere but was from Newbury.
I did not find any baptisms for the other children listed on the 1815 Toomers census in the St Nicolas parish records but familysearch does have one for an Edward Pearce son of John and Elizth Pearce on 13th May 1804 at Highclere Hampshire.
Interestingly there was this baptism in St Nicolas Newbury which might relate to your John Pearce:
Eliza illegitimate daughter of Sarah Tranter
Born 16th January 1810
Baptised 9th February 1810
Reputed father: JOHN PIERCE
and this burial:
St Nicolas Newbury
30th June 1830
Elizabeth wife of John Pearce
Aged 54
I am wondering if this is John remarrying in 1830
Marriage date 21 Nov 1830
St Nicolas Church Newbury
Groom: John Pearce
Groom's condition: Widower
Bride: Elizabeth House
Bride's condition: Widow
Chris