Hello Ann and Pauline, please correct me if the information is not right,

is your Robert Garrett married to Catharine Caley 21 June 1764 Lezayre,

usual age at time of a first marriage is around 20 years of age,

if Robert was born in 1725 he would be age 39 at his marriage in 1764

if born in 1739 he would be age 25 at marriage in 1764

my thoughts are that he is the Robert Garrett baptism, Robert Garrett 9 September 1739 Lezayre, Son of William Garrett and Mary Kewn

Will for Mary Garrett als Kewn on Brian's website, www.lawsons.ca

marriage, William Garrett and Mary Kewn 12 Feb 1725 Lezayre
baptism, Robert Garrett 9 Sep 1739 Lezayre

hope this helps,
Averil