If they were residents of Boston-years ago there were a whole series of
transcription of Mass early Vital Records from Twon earliest days to about 1850's. Check for Mass Library that hold copy of Boston Vital Records from date of founding to 1850s'; these records were divided
into birth/marriage/death and were further divided by ethic race-white/Indian/"Negro" (blacks)-if Phillips was a resident of Boston
possibly there are vital record.