Children who move back home with their parents need to talk about boundaries, and parents need to not over-reach to help them.
Psychological Society of Ireland President, Anne Kehoe, has said adult children moving back to the family home can mean a hit to their self-esteem.
While parents can over-compensate for having their children back in the house.
Dr Kehoe told The Hard Shoulder moving out has become more difficult for more people.
"We're designed to individuate, or to move out of our family of origin, and start our own families - have our own space and inhabit that space," she said.
"It's tricky these days when that is made more challenging for people, and the expectations are difficult.
"If you think about the parent's time, it would have been much more... acceptable - most people would have moved out.
"Whereas nowadays, anyone in their late 20s, 30s into 40s, 50s it's a harder market.
"The housing crisis is really in full flow".
Dr Kehoe said it can be easier to navigate for those who have moved back, rather than those who never left.
"If someone has moved out before and come home, things will have changed in the house," she said.
"That is much easier to put in rules and regulations when you can say, 'This is how we do it now.'
"But if someone has been there all along that can be harder to do, as you're renegotiating there.
"Really it's about expectations, and some people can have unrealistic expectations about what will be done for them or what they will have to do for others.
"It's having those awkward conversations where you say, 'This one little thing you do is really annoying me, and here are the rules of this house'".
Dr Kehoe said enforcing rules can sometimes be easier when dealing with strangers rather than family.
Dr Kehoe said parents can sometimes overcompensate for their children.
"If you think about a parent who wants to make lots of room for their adult child who's having a tough time... they want to give them all the allowance they can and make up for how it feels to live back at home - possibly by over-doing things for them," she said.
Children too can revert to old habits, Dr Kehoe said.
"You see this around Christmas time when everybody comes back together," she said.
"The dynamics come back of someone [who] maybe always has to do it their way, or someone is pushing against that.
"That's the trouble with being at home if you are a grown, independent adult.
"You might revert to being more of a teenage self, especially if you're having a row.
"All the old hurts and all the old things can come up... it would be much easier if you were with strangers - that wouldn't happen".
What advice does she have for both parties?
"For the adult children living in their parent's houses: having this conversation out loud is important," she said.
"They can have a lot of - because it was different in the old days - a lot of shame or guilt or self-esteem issues around it.
"It doesn't feel good on your mental health, if that's not where you want to be and you're stuck there.
"For the parents: they are your child and you love them as much as you do, but the important skill for any adult to have are independence.
"What you'll find is parents, in trying to make it up for whatever [reason], they might be over-functioning where they're doing jobs that a grown adult should be doing for themselves.
"They should try and hold back on that, because that's where the resentment builds," Dr Kehoe added.