This baptism information was at the kind hands of Antony Mount a deseendant of the William Mount whose second wife, but not Antony's ancestor, was Elizabeth Girle who is my 6th gt Aunt.

The record clearly spells Phillip with two ‘l’s but the names had to have been after Philip Meadowe, his grandfather and his grandfather and all the descendants of his brother's who had the name Philip spelled with one 'l', so I am taking this double-l spelling to be an error on the part of whoever entered the baptism register.

[subsequent note: the entries for both Philips were spelled with the double ‘l’ so I reckon it was a common spelling then.]

Philip's baptism transcription from Ancestry from London Metropolitan Archives:

Name:              Phillip Powys
Record Type:       Baptism
Birth Date:        8
Baptism Date:      9 Jul 1699
Baptism Place:     St Giles in the Fields, Holborn Camden, England
Father:            Thomas Powys
Mother:            Elizabeth Powys
Household Members:
Name :
Thomas Powys
Elizabeth Powys
Phillip Powys
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The actual text on the baptism register is:

  "[July 1699] 9 Phillip Son of Sr Thomas Powys & Elizabeth his wife born 8th instant"

This gives his brith date as the 8th of the same ('instant') month.

All the above confirmed from a faint copy of the Baptism register, obtained in 2021.

And I have also found the copy of his burial entry which reads:

[ Parish of Saint Giles in the Fields, St Giles High Street, Holborn, London ]

”Burials
July 1699
. . . .
27 . . . . Philip of Sr Thomas Powys”

My guess is that he died no more than 48 hours before his burial.

So he lived a bare 18 days.
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While nothing has been found about his birth, it is very likely that his brother, born in 1704 was also given the name Philip in memory of this Philip and because he had already died.  On this basis, this Philip died before 4 April 1704.
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