05/05/2016 13:15 BST | Updated 06/05/2017 06:12 BST

How to Find Stepfamily Harmony

Stepfamilies are the fastest growing type of family in the UK, but in many ways they represent the wild west of family life. There are no clear rules, very little advice and few good role models (especially in fairy tales).

I found this out for myself both as a psychologist studying stepmothers and personally, when I met my now husband, who had an 18-month-old son from his previous marriage, while I had a three-year-old son and a daughter aged six. I went into these new circumstances thinking - 'I'm already a mum, how hard can it be?'

This turned out to be naïve. Not because I hadn't thought it through, but because you don't even know what the issues are until you face them. Being a stepmother was more difficult than I had ever imagined, and if someone had told me then that it could take seven years to build a family I would have been shocked.

For my academic research at Regent's University London I interviewed 250 stepmothers and discovered they had significantly higher anxiety levels and depression than biological mothers and they also had poorer support than biological families.

It is believed that nearly one in three UK families includes stepchildren, and this could result in a lot of anxiety and stress we could do something about if there were more support and advice for stepparents.

I often see couples two years into their stepfamily experience when they're thinking, 'hang on, I didn't sign up for this.' This is why it's vital to know what to expect as a stepparent, how to navigate the pitfalls, and above all how to be realistic in your expectations.

No, you don't go off immediately and live happily ever after, although there are plenty of happy endings. The rewards can be incredible in the long-term: our children are now 22, 19 and 17 and we have built a very happy family together.

Here are some pointers for building a successful step-family:

1. You won't love your stepchildren at first

A common myth is that you will automatically love your stepchildren. Sadly this isn't reality. Be respectful, build trust and hopefully those feelings will grow.

2. Your house, your rules

Don't be afraid of setting house rules that may be different from their biological parent's. Thank them when they remember to do something as it will encourage them to do it again.

3. Have realistic expectations

Research suggests it's quite normal to take seven years to build a happy, successful, functioning step-family. Even the fastest families take four years before everyone is comfortable.

4. Build your relationship with your partner

Couples with stepchildren miss out on the initial years when it's just the two of them together. This makes it vital to make time together and talk.

5. You won't get any thanks

Biological parents understand children don't thank you for changing their bedclothes, but it can be a shock to a new stepmum. Expect gratitude from your partner who can help restore the balance.

6. Find something to share together

It's much easier to share something new with younger children, perhaps planting seeds or cooking, and with older girls shopping ticks most boxes. With my stepson it's watching Doctor Who.

7. Don't try to be a parent early on

If your stepchildren are younger, think of yourself as an aunt or godmother figure. If they're older or you don't have any parenting experience, start by being a friend to them.

8. Put yourself in their shoes

It can help sometimes to think about what stepchildren are going through. It's the couple who have got together - the children have not asked for any of it.

9. Create your own traditions

It's important to build your own traditions and memories. Family mealtimes are an important 'glue.' You're not aiming to be The Waltons, but one shared meal during the weekend is realistic.

10. Toddlers and teens are different

The last thing any teenager wants is another parent when friends are more important, so try saying, 'you have a mum and dad and you have me as well as an extra person who cares about you.'

Dr Lisa Doodson's new book: 'Understanding Stepfamilies - a practical guide for professionals working with blended families' is out now.