My database shows that Jonathan Seaver born 20 Dec 1753 died June 1820 in Boston. I think this was in the Boston newspaper Columbian Centinel or similar, I can check my notes if you'd like.
I don't have any info on the parents of Margaret Harris - I checked IGI and AF and didn't see anyone obvious. She may be in Boston birth or church records. I have that she died August 1826 in Boston, aged 67 (so that makes her birth ca 1759).
My data on Patience Trescott says she was born 20 Mar 1722/3 in Dorchester, daughter of John and Sarah (Topliff) Trescott. This is info from Dorchester VRs and IGI - not proven by anything else. But, the given name is fairly unique!
Regards -- Randy