Ian’s daughter Libby was using Instagram to post images of her self-harm injuries.
He says photographs on the social media platform were more graphic than things he had seen when serving in the Army.
Libby is now in recovery and hopes to become a paramedic.
In a statement, Instagram said it had begun “a full review of our policies, enforcement and technologies around suicide and self-injury content”.
If you’ve been affected by self-harm, eating disorders or emotional distress, help and support is available via the BBC Action Line.
