MIA FREEDMAN: Memo to mothers and future mothers: you will miss milestones, and that's OK.

My son’s second birthday happened without me. If he had been my first child, this would have gutted me. Because nobody imagines they will ever miss important moments in the lives of people you love, especially ones who came out of your vagina (or sunroof).

But Remy is my third child and by the time you get to number three, you are more sanguine. Your expectations for life going the way you’d planned are considerably lower. You’ve marinated in reality enough to know that the universe gives no f**ks about your plans.

In the days before my son’s birthday, after months of begging, I’d finally been granted an interview with then Prime Minister Julia Gillard. It was during the 2010 election campaign and the only available time she could sit down with me was during a flight she was taking from Melbourne to Sydney that was leaving at 7am. If I wanted to talk to her, I had to be on that plane. This meant I had to fly interstate the night before and my son would wake up without me on the day he turned two.

Kids have no clue what a birthday is when they turn one. It’s not until number two that they work out it means something – cake, attention and new toys. Do you remember your second birthday? If you do, it’s probably because you’ve seen photos of it and created a memory. You don’t really. That’s what I kept telling myself when it became clear I wouldn’t be there for my son. I won’t pretend I didn’t feel some guilt. Emotions ran high actually.

But my husband, ever practical in the way I find men are with these sorts of things, had a great solution: let's just move his birthday. It's not like our toddler had a Google calendar. Or a Facebook account to remind everyone it was his birthday. So we did. I flew to Melbourne for work and we celebrated as a family the next day. This worked a treat for him and also pretty well for me.

And now that he's old enough to read this, I still think he'll be cool with it. The important part is the fact he got to eat cake as a main meal.

Watching the media coverage of Prince George attending his first day at school this week, my heart squeezed a little for his mother, Princess Kate, who was no doubt doubled over with the severe nausea that plagues her in the first months of her pregnancies mixed in with dismay at missing her firstborn's big day.

I looked at this picture and I thought about how hard it would be for her to see......

That was meant to be Kate, holding her little boy's other hand and the fact she wasn't there will no doubt be as hard for her to swallow as solid food. It's not fair. It's not right.  And it's not. But when you become a parent, you need to learn to accept not being there for every milestone, every concert, every sports game, every triumph and disappointment. Your child will kick goals and win prizes and have birthdays and lose a tooth and do many, many things that you will miss because you're human.

Of course every parent's greatest fear is that something will sever them from every milestones. That's the fear that turns our blood cold and our stomach to acid. I went to the funeral of a beautiful little seven year old boy last week, Millar Munro. What his parents wouldn't give to spend just another hour with him, another minute. They treasured every milestone, every tiny victory, every waking and sleeping moment in the last year of his life.  The remarkable Connie Johnson, who we lost on Friday, knew for years that the milestones she would spend with her children were finite and she needed to cram in as many memories as she could because there were many she would miss.

But for those fortunate enough not to be searching with urgency for light in the dark shadow of a medical diagnosis, it's important to lower the bar a little. Adjust your expectations around what you'll be there for and accept the inevitable reality of missing milestones.

This is why Work Life Balance is such a damaging myth, especially for women. If only it were as simple as deciding that you'd like have balance in your life thanks very much and then working steadily towards achieving it.

Listen to Mia Freedman, Holly Wainwright and Jessie Stephens discuss what's been a big week for the royal family on Mamamia Out Loud. Post continues after audio...

As the kids say: lol (the kids don't say that apparently, only sad, old people say it which is why I'm saying it).

You don't get to choose when life happens to you. Life doesn't care even a little bit about your balance. It laughs at your balance. Life thinks balance is bullshit. It couldn't give a toss that it's your kid's birthday or their first - or last -  day of kindy. Life doesn't care about these things because life is way too busy throwing cricket balls at you and expecting you to catch them. Career opportunities. Business opportunities. Pregnancy. Pregnancy complications. Anxiety. A new relationship. Breakups. Migraines. Financial dramas. Miscarriage. Parents with health problems. A wedding. Friends with cancer. Endometriosis. A funeral. Mental health challenges. Breast cancer. Your dog going missing. Divorce. A business trip. A car accident. Chronic back pain. Your child being bullied. Losing your job. Getting a promotion. Getting the flu. 

Because none of us have the ability to dodge life (nor would we want to, considering the alternative), it means there are times when you simply can't put your child first. I don't mean if they're bleeding or when they really need you - this isn't justification for neglect. But sometimes, when you can't be there, you teach your child something in your absence. By not being there - and explaining to them why - you teach them something really important about the world and it's this: they are not always the centre of it. A child must feel safe and secure and loved. That's the absolute lowest common denominator of parenting. But they must also learn that other people have needs and that sometimes those needs must take priority over their own and that's OK. It doesn't mean they're not loved or safe or secure. It just means that their mother (or their father) cannot always be there for everything.

Earlier this year, my husband and I had to go to New York for work. We left our youngest two with our eldest child (you can read that entertaining tale of his two weeks as a 'single dad' here) during the start of a new school year. We missed it. They were OK (the same can't be said for their older brother who still hasn't recovered).

Next week, my daughter has something on that I can't attend. As every parent with a school or kindy age child will tell you, the world has changed a lot since we were kids. I don't remember my parents ever coming to my school. Maybe once a year? Maybe? But now, for better or worse (worse, grumble a lot of working mothers I know who just cannot take any more time off work), you are expected to attend at least a dozen events a year at your child's school, usually during the day. And if you have more than one child? Do the maths (actually, maths seems to be the one subject that doesn't ever demand parental attendance for any kind of performance which I really appreciate).

Anyway, when she told me about it, I felt that familiar punch of guilt and launched into my "I"m so sorry but..." speech but she cut me off to breezily reassure me it was totally fine so long as someone came. Done! A quick text to the grandmothers and it was sorted. This is why it really does takes a village.  Without extended family, friends, sparents, aunts, uncles and other loving adults around our children, it's really tough for any parent to be there for everything. We need help.

Prince George won't remember anything about his first day of kindy (his lunch looked pretty good, frankly so he may remember that)  but his Dad will. "William's got this," I thought to myself as I watched the footage of him taking his little boy by the hand and gently leading him into the classroom in front of 600 people pointing cameras at the small Prince. And while Kate will forever feel the pang that she missed out on the experience of that milestone (so often what we feel as guilt for our kids is actually disappointment for ourselves at missing out on a moment of joy which is totally valid and understandable - you want to bank as many of those moments in life as you can), her little boy's experience of his first day at kindy won't be any less because his mother was too sick to be there.

Resilience is built in large part from the ashes of disappointment. And fear. From experiencing challenges and learning that we can meet them even when circumstances (and attendance from loved ones) aren't always ideal. So next time the strife of life wedges itself inconveniently, frustratingly, maddeningly between you and something you wanted to do but couldn't, remind yourself that you had to make a choice. And hopefully, you'll be there next time. And it's OK.

If you're a parent, what milestones have you missed? If you're not, what did your parents miss?

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Mia Freedman is the co-founder of Mamamia Women's Media Company. She is a proud patron for Rize Up, the charity supporting women and children fleeing from domestic violence, an ambassador for Share The Dignity, the charity which provides sanitary products to vulnerable women who are homeless, disadvantaged or the victims of domestic violence and an ambassador for Sydney Dogs and Cats home, a no-kill shelter where thousands of animals are rehomed with forever families. She is also a proud supporter of Ladystartups, an initiative she began to support women who have started their own business.

She is the author of the best-selling book Work Strife Balance for every woman who feel like she's the only one not coping (you're not) and the host and co-host of three podcasts: No Filter, Mamamia Outloud and Tell Me It's Going To Be OK (even though Trump is President).

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