My mother in law couldn’t believe the question posed by her 3-year-old granddaughter last winter.

“Can you say metamorphosis?”

My mother in law called me the next day to tell me the story. I knew immediately where my daughter had heard the word: “Little Einsteins: Our Huge Adventure.” It was one of the first DVDs we got her and she was obsessed with watching it for a couple of weeks. In the movie, the young geniuses help a young monarch caterpillar on its journey to become a beautiful butterfly.

But it got me thinking that I didn’t really know what metamorphosis entailed. My seemingly precocious child probably knew more about it than me.

So a couple of weeks ago, when I spotted four caterpillars — two white fuzzy ones, a yellow, white and black one, and a generic brown one — all within a few days, I decided to bring them into the house to see what I could learn. It turned out to be a great biology lesson for the whole family.

I got three jars and put the different varieties in separate homes. I closed off the top with a net-like tape. I got online and immediately learned they probably would eat only what I found them on. Every day I went out and found fresh leaves — a different kind for each caterpillar. They ate voraciously and I found the more they ate, the more I had to clean out those jars.

I kept them on the kitchen table and the Rasp girls, ages 15, 11 and 3, and I watched their progress pretty intensely for a week or more. We discovered the white, yellow and black one was a monarch caterpillar. We got him out, held him and took pictures. We also learned the white fuzzy guys probably had prickly hairs that would stick us.

The white caterpillars spun themselves separate cocoons and, despite their opaqueness, we watched intently, eager for them to show off their transformation.

Meanwhile, the monarch continued to eat and grow exponentially. The brown caterpillar disappeared under some dirt in his jar. I later found he had morphed into a hard, dark brown chrysalis. He later transformed into a small moth.

Just before the fuzzy white guys showed off their beautiful white moth wings and yellow spots, our favorite, the monarch, situated himself upside down, hanging from the top of the glass jar in a J-shape. By bedtime, he’d started to turn slightly green. When we woke up the next morning, our pet had entered the pupa stage of metamorphosis.

Not much happened for more than a week. Then on the 11th day, my mom, who had arrived for a visit the day before, saw the now transparent pupa move. She had become just as enthralled by the metamorphosis as me. We watched as, in seconds, the butterfly crawled out and hung on the thin shell. It’s wings were wet and he wasn’t very agile.

We put him (or her) in a large clear bowl and admired him for most of the day. When it appeared he might be ready to take flight, we put him on a flower in the front yard and took pictures and admired his beauty. When we finished, he flew into the tree.

It was a great learning experience for the entire family. At least now when that precocious kid of mine asks about metamorphosis, we’ll not only know how to say it, we’ll know what it means.