My husband thought he was too old to be a dad at 55. But it was the best decision we've made.

• Robert de Niro and Al Pacino made news for having babies at 79 and 83.
• My husband and I went through years of trying to adopt a child.

The news that actor Robert De Niro recently became a father again at the age of 79 has sparked a lot of debate around the world as to whether he's too old to be a new dad. His wealth and status probably mean there's a lot of help around him. But how old is too old to become a parent?

This is a question my husband and I are very familiar with. We met when I was 26, he was 35. Fast forward 10 years, and it became clear we weren't going to be able to be birth parents without a lot of intervention.

For us, becoming parents was more important than the way it happened. Adoption had always been something we'd talked about and felt like the best route to parenthood for us. In the UK, the assessment process is in two parts. The first culminates in an approval panel where a group of people you've never met get to decide whether you can become parents. You then start the matching stage to find a child within your criteria in terms of age and the issues they face.

We started matching with potential adoptees 15 years after we met

When we started matching, I was 41, and my husband was 50. We had a long and difficult 10-month wait before we found out about our daughter. She was six months old.

We'd had lots of discussions with our social worker about my husband's age and whether he was too "old" to be a dad to a young baby. The conclusion was always that he wasn't. He is fit and healthy and has a young outlook on life.

So, our daughter came home, and we settled into life as a family of three. Other than not being able to cope with lack of sleep as well as he did when he was younger and his body aching a lot more, his age was never an issue.

Fast forward a few years, and we found out that our daughter's birth mom was pregnant again. Her circumstances hadn't changed, so the plan for the unborn child was adoption. Our social worker asked if we wanted to be assessed as adopters for the sibling.

He worried about being too old

My husband's initial reaction was that he was too old. He was in his mid-50s, and although he had no health concerns, he was worried about the numbers on the page. He'd be getting towards 70 by the time she left school, and worried his age would bother her.

But then we started to think about it from our eldest daughter's perspective. Saying no because we were worried about what she — and her sister — might think about his age in the future felt wrong. And we'd be denying her the chance to grow up with her sibling because of that. In the UK, adoptions are usually closed, which means there's no face-to-face contact with the birth family. So, the only contact our daughter would have with her sibling would be via annual written updates.

She was 4 when her sibling was born and was desperate to be a big sister. We live in a society where the retirement age is older, and people tend to live longer. We felt growing up with her sister would be more important to our daughter than her dad's age.

So, we said yes, and about eight months later, our youngest daughter came home when she was almost 6 months old. My husband was 55.

We knew we'd made the right decision when we saw the love and happiness on our eldest daughter's face the first time she met her sister. They adore each other. They fight a lot too. But they share a bond that will help them through whatever the future holds. For them, that's far more important than age.