Death. Stranger danger. Childbirth. When I offered to have my daughter's best friend for a day during the school holidays, I wasn't expecting five-year-olds to cover such heavy topics in a few short hours.
How are you meant to reply when they ask: "Why is there a man trying to steal children?"
Or: "How old you are when you die?"
Google or basic general knowledge can cope with why the wind blows and the like, but that only gets you so far.
Because our 3-year-old boy was in daycare, I had agreed when my girl invited a third friend too.
As we all know, a threesome can change the dynamic so I was listening out for any ganging-up or bratty behaviour.
That side of things was mostly okay but there were some surprisingly intense discussions, which began first thing in the morning, when I took two of the girls to the supermarket, before collecting girl number three.
As we wandered along the meat section, my girl's friend announced:
"I came out my Mum's tummy, not her vagina. She's got a cut I came out of and you can see the scar."
That's exactly what everyone wants to know first thing in the morning.
My girl replied: "Yeah, my Mum might have to have that too because our baby is being a little rootbag."
Wow. I'd done my best to keep it light-hearted when I had explained to our girl that I might need to go to hospital for the doctors to take our baby out in a few months.
I'd mentioned this purely to explain that she might wake up to one of our friends looking after her and her brother one morning, in case I have any complications that send me to hospital unexpectedly.
Only, the word I had used was that our baby was a bit of a RAT-bag.
Other public announcements from these two littlies that day included (in a crowded café): "You have to drink lots of water or else your wee goes really yellow."
There was also significant discussion about the "man who steals children" after some recent reports of someone approaching children in Tauranga. Then the conversation turned to death.
Worried the girls would leave traumatised, I had some explaining to do when I returned them to their mums. I did my best to keep the topics as light and factual as possible.
I told the girls their mums and dads were always very close to them anyway and they knew what to do if a stranger approached them (run away to an adult and tell them to call the police).
Death was a little trickier, but as it had come up in the context of one of them mentioning the 2016 Dreamworld tragedy in which four people died (seriously!), I said sometimes people did things that could be scary because it was fun, like when they climb high things at the park and feel a bit scared, but excited too.
And I reminded them that no one was going to make them do anything they didn't want to. It was a politician's subject-change if ever I saw one but what was I to do?
The thing about five-year-olds is that while still quite innocent, they have enough knowledge to challenge things and they are insatiably curious, with questions beyond what many adults have the answers to.
The day also brought hilarity of course, but it did leave me once again questioning my adequacy as an adult.
The following day we went back to making paper aeroplanes.
At least Google has answers for that.