鈥淭his is the stupidest thing ever,鈥 my daughter whispers to me through gritted teeth, squeezing my hand a little too tight as we shuffle along with our group.

We鈥檙e on a Harry Potter walking tour through the streets of London -- a tour for 鈥淢uggles鈥 that I thought the 10-year-old would adore since she鈥檚 already halfway through her seventh back-to-back Harry Potter book of this trip so far.

When I found the tour online, she had sounded excited to go, and though I balked a little at the $55 price tag, I patted myself on the back for finding what sounded like the perfect mother-daughter afternoon. She would see all the film locations, and I鈥檇 get to visit hidden parts of London I hadn鈥檛 yet explored. Wins all around.

But as we pushed through the cramped Underground that morning, hurrying to the tour meeting point, my daughter stopped dead in her tracks as she spotted the rest of our group.

鈥淲hat is this?鈥 she asked.

鈥淯m, it鈥檚 the walking tour we鈥檙e doing?鈥 I replied.

鈥淲alking tour? You said this was a museum,鈥 she said in disbelief.

I swear I didn鈥檛 say anything about a museum, but somehow, while telling her we would be seeing the real-life London film locations of the movie series, she had gotten it into her head that we were going to an exhibit, not a walking tour.

And now, as she watched the tour leader calling out to the group to huddle in as London morning commuters rushed past, I realized she was going to hate this.

My quiet, reserved daughter can鈥檛 stand the idea of anyone deliberately drawing attention to themselves by speaking up in a crowd. Yet here was the tour leader, beginning to move us through the busy Borough Market, pointing to a doorway and loudly explaining that this site was the stand-in for the entrance to the Leaky Cauldron.

鈥淐ould he not talk so loud,鈥 my daughter angrily whispered. 鈥淭his is stupid. I want to go home.鈥

Uh, we鈥檙e not going home, I told her, not after I shelled out this money.

We pressed on, me hoping she鈥檇 come around as the tour wore on. But even two hours in, her mood never lightened and we left the group the first chance we got as it began wrapping up. The day was a disaster, the tour a failure, my perfect mother-daughter outing a washout.

Disappointments are nothing new to parents and they鈥檙e nothing new to seasoned travellers either. Visit enough places and you鈥檙e going to eventually encounter a few duds. But somehow, when you鈥檙e on a huge journey, , these disappointments hurt a little more.

This is supposed to be the trip of a lifetime, you tell yourself. Every day has to be fabulous. There isn鈥檛 going to be another chance to do a trip like this, so everything has to go right.

But of course, not everything can go right. It鈥檚 just the laws of statistics: the longer the journey extends, the bigger the risk for small disasters.

Mercifully, we鈥檝e had no major disasters on this trip, so far. But we have made our share of mistakes. We stayed in one town a little too long, for example, and when we ran out of things to see (or at least sights we could afford to see), we began driving each other crazy by holing up in a too-small apartment, getting into arguments and on each other鈥檚 nerves. Though my husband was happy to stay in that town longer, the rest of were ready to move on, but couldn鈥檛.

And there remains the fundamental problem of long-term family travel: it鈥檚 impossible to plan for what everyone will need from the journey. With short vacations, it鈥檚 simpler. When you book a week at a family resort or cottage, everyone knows what they鈥檙e in for: lots of relaxing, some beach time, some sunsets. A trip to a big city, you鈥檙e there to see the sights. You end the vacation happy because everyone got what they expected

But with longer family travel that goes on for months, it鈥檚 not so simple. Eventually, your travelling styles clash.

I鈥檝e learned I tend to get itchy feet after about a week in a new place. While my husband is happy to just hang out in cafes and read the local newspaper, I start worrying we aren鈥檛 doing enough, not seeing enough of the rest of the country, not getting maximum bang for our travelling buck. I also tend to be more interested in seeing the natural wonders of a new place, the countryside, while my husband prefers cities.

Or, at least, he thought he preferred cities.

We recently found ourselves in a small cottage outside of Killarney. My husband hadn鈥檛 been much interested in seeing that part of Ireland; he really preferred the rich history of Dublin. But I booked us a cozy cottage out of town that happened to have a woodstove. In Ireland, most fireplaces burn peat for fuel, not wood, and I quickly learned peat is more difficult to light than you might think. Okay, to be quite honest, my first attempt at getting that fire going ended in a smoke-filled mess.

鈥淢ove over, move over. This is a man鈥檚 job,鈥 my husband said to me with a grin, as he pushed me aside and got to work building up a new fire.

He spent the rest of the evening happily tending to that fire -- and every fire each day after that as well. He gathered up peat strips from the woodpile and chopped up hardwood logs using an axe to make more kindling, and soon the kids were learning to do the same using hatchets.

鈥淚 love this place,鈥 he announced to me the second day. 鈥淐an we stay here another week?鈥

鈥淵eah, yeah!鈥 the kids chimed in. 鈥淐an we? Can we?鈥 They too had quickly fallen in love with the place, the kindling, and the dogs who lived on the property.

鈥淏ut I thought you didn鈥檛 like the countryside,鈥 I teased my husband. 鈥淒idn鈥檛 you tell me you wanted to stick to cities?鈥

鈥淲ell, I was wrong,鈥 he admitted.

That stay in the 鈥渃ountry鈥 turned out to be exactly what we needed just then, and made it clear to us that it had been a mistake to just focus on cities.

Yet it鈥檚 a mistake we never would have foreseen when we planned the trip. We鈥檙e realizing though that you kind of learn as you go on long-term travel. You can鈥檛 predict how your needs are going to change as you go.

Which is why I鈥檓 now glad we didn鈥檛 book every single thing before we left. We mapped out the basics and we booked the flights, but we also took the advice of others who had done similar long journeys and built in some flexibility. That way, when mistakes happen, we can brush it off, make a shift and press on to the next great moment to come.