Amy, who died from alcohol poisoning last July signed the hand-written notes 'your wife' despite their split.
“In one letter Amy wrote that Blake was definitely getting her pregnant within two months. She talked about conceiving the baby — which they would call Lucky — on Valentine’s Day,” Georgette told The Sun.
“Even after their divorce Amy told Blake she’d love him forever. They carried on talking to each other until a few months before she died.”
Amy met Blake in 2005 and the couple married in Miami in May 2007 just a month after becoming engaged, but split two years later.
Georgette said her troubled son showed her the letters last year, before he began a jail sentence for burglary and fake gun possession.
“Blake has a tarnished reputation but he and Amy were in love. They fell in love and drugs got in the way.
“The letters show Amy was totally in love with Blake. She was besotted – she called Blake her proudest achievement.
“The last letter must have been in March 2010. She told Blake he knew her better than anyone.
The letters also reveal pet names the Back In Black singer gave them both. Amy called herself a mermaid to Blake's sailor and a lioness to his lion.
“I remember odd phrases she used. They were very Amy. She said they were ‘twinnies’ separated at birth. There were cartoons, drawings, and doodles.
“I got goosebumps when Blake showed me them. The DNA of their relationship was all there.
“But there was a dark side. She also called Blake her most precious poisonous possession."