Reading this, I feel slightly embarrassed about our largely unplanned 100 km family cycling tour to France 1.5 years ago. We used our standard day-to-day Peugeot bikes from the 70ies, and a relatively new children's trailer. Because our bikes were so old, I made sure to have all the tools with me to fix anything broken, despite the relatively short distance. The bikes didn't have a single mechanical failure, not even a flat tire. But halfway through our trip, the trailer had a broken spoke. I removed the spoke, hoping that the rest of wheel would hold together, but all the remaining spokes immediately started to become loose after a few kilometers. I ended up truing the wheel using the remaining spokes, and than fixating the spoke nipples to the spokes and the rim with a pack of kid's plasters. To my surprise, this actually worked. We made the remaining 50km without problems, but stopped every kilometer or so to check if any spoke had become loose.
Note that we largely cycled through the French and German countryside on dedicated bike routes on which we were the only cyclists most of the time, so this was relatively uncritical.