Rex Features
The Sabrina The Teenage Witch star will chronicle two-year-old Mason's learning process for the next two months in a bid to help other parents.
Hart, who gave birth to second son Braydon in March, is taking part in a new Pull-Ups training pants project to mark Potty Training Awareness Month.
She said: "When Mason first showed signs that he was ready to use the potty, my husband and I were really excited and - more than anything - proud.
"Potty training is one of the first times I'll be able to act as a teacher to my son, and that adds a little pressure."
