Something very strange happens when you get married. And then again when your kids get married. You acquire in-laws. It can even happen if you or they are simply involved in a close partnership.

You suddenly have a lot of new people in your 'family' who you didn't choose, but who you're supposed to be friendly with. There are their parents, sisters and brothers, and their spouses and on and on.

And we all know it can cause a lot of problems.

Of course there are some who just love their in-laws. I know a woman who insisted that her daughter-in-law should be known as her 'daughter-in-love' from the very beginning. How lovely for everyone.

I also know people who go on holiday with the whole extended family – children, their spouses, and loads of grandchildren. Some do it every year. They are very lucky to get on so well.

More frequently, we just cope. It is hard enough with the parents-in-law, not to mention other members of the family. But somehow, we usually learn how to manage. We work out what foods they eat when they come for dinner, what subjects you should avoid in conversations and, best of all, what interests you have in common.

Sometimes, they live nearby and you end up seeing each other frequently. Sometimes, everyone does their best to see each other as little as possible.

But when the grandchildren come along, it is a whole different story. If you want to see the grandchildren, the son or daughter-in-law comes too. It is part of the package.

If it is your son's baby, especially, it is hard to avoid his or her mother.

Of course, a baby can be just the thing to cement relationships. You share the love of this new being and that papers over a whole lot of cracks. Indeed, you may well be very impressed with how your son or daughter-in-law handles their new baby, improving your relationship with each other and making your time together even more agreeable.

Yet this is also where the greatest problems can arise. You go to visit the new baby or, later, the growing children, and however much you love the grandkids, you may not agree with their parents' ideas about how to bring them up. Often it is the daughter- or son-in-law whose ideas are the most divergent from your own.

They may not have your ideas about how to feed them, play with them or what to buy as presents. They may have loads of rules, when you believe in freedom, or vice versa.

And you might be tempted to give advice, but do not want to be irritating. 'Every new granny should be issued with a zip', one friend said, and it is true.

Who says being a granny is always easy?

Ann's most recent book is Celebrating Grandmothers: grandmothers talk about their lives, which is published by New Generation and available from Amazon, and you can find out more about Ann on her website.