An image of the deceased pet and the dates of birth and death can be placed on the stone through laser engraving.
The pet's name is carved into the stone and the owner can choose to add a poem, some text and/or the dates of birth and death.
Estate Records - These may contain everything from personal and real property to names, dates of birth or ages of heirs.
These records contain a great deal of information on the deceased, as well as the heirs, including ages and perhaps dates of birth.
Tombstones - This is a valuable source for dates of birth as well as dates of death.