First Appearance: Episode 387 (1984)

Last Appearance: Episode 692 (1985)

Known Family: Husband - Mike O'Brien; Daughter - Katie O'Brien; Son - Jeff O'Brien; Brother-in-Law - Jim O'Brien

Key Relationships:
Marriage to Mike O'Brien (d. 1985)

Key Storylines:
Heather Townsend met Mike O'Brien in Melbourne after spraining her ankle as she was passing the building site where Mike was working in the early-1960s. Mike offered her a lift home and she accepted. He then asked her out and the relationship went from there, leading to marriage and children: Katie and Jeff. The family moved to Perth in the early-1970s. Mike set up a building company with his brother, Jim, but, over time, he gradually started working longer and longer hours, and it got so that Heather and the kids never saw him. In the end, the pressure on their marriage became too much, and, in the early-1980s, Heather left Mike and took the kids to another part of Perth, where she raised them on her own for a couple of years.

When Mike's company went bust, he and Heather decided to try again. Mike admitted to Heather that he'd had a bit of a fling with his secretary, Carol, while he was single again, and she told him to see Carol one more time and finish things properly. In late-1983, Heather had to deal with Jeff and a friend of his, Luke Carlyle, stealing a car, going for a joyride and crashing it. She ended up turning to Jim, who took full charge of the situation and covered the costs. Jeff appeared in a children's court but was released on a bond and no conviction was recorded against him. Heather decided not to tell Mike about this, though. Heather worked for Roger Carlyle - Luke's father - but worried about his unhealthy interest in young girls; she feared particularly for Katie's safety around him. Having reconciled with Mike, the two of them decided to move the family back to Melbourne and start again.

Life in Melbourne doesn't run smoothly, though: Heather has to deal with Luke turning up on the O'Briens' doorstep, followed by Roger; Roger trying deliberately to destroy Mike's new lawn-mowing business; Mike's furious rows with his brother, Jim; Jeff's descent into steroid abuse and then alcoholism; Mike's new job working for Patricia Morrell - and the increasing number of hours he begins to work again; and then Jeff's untimely death in a fire at the O'Briens', which also leaves the family homeless.

Looking for a second chance in life, Mike and Heather adopt a baby boy called Jamie, not realising that he's really Beryl's baby son, Robert, who was kidnapped firstly by Gloria Dutton and then by Leigh Palmer. They move away to Brisbane, to make a new start - but then have to face further trauma when Beryl discovers the truth and turns up demanding her baby back. Heather refuses and Beryl eventually backs down, accepting sadly that her son has a new life.

A few months later, Mike is injured in an accident on a building site, after feeling unsteady following a bout of 'flu. He appears to be making a recovery in hospital, but the doctors then discover a blood clot on his brain. They announce that it's inoperable and Mike dies towards the end of 1985. Deciding she can't bring up a child on her own, Heather heads back to Melbourne and returns Robert to Beryl. She finds it hard to let go of 'Jamie', though, and tries to take him back to Brisbane again - only she's stopped by Beryl and David. She has to head home to Brisbane on her own to come to terms with all the tragedy of the last couple of years and the sad realisation that life has to go on...