Nobody was using the old wren house.

My grandfather built it. Grandpa started building birdhouses when he retired from milking cows and his second oldest son took over. That son, my mother’s brother, is now 87 and retired 20 years ago. It’s a pretty old birdhouse.

“My dad never built fancy birdhouses,” my mother explained. Grandpa put on a tarpaper roof and, if you needed to clean it out, you had to unscrew the back. But they were sweet little birdhouses, painted bright blue with a little perch outside the round door. I always assumed they were mostly for decoration.

My parents had one of grandpa’s birdhouses hanging outside their cabin for years and they got wondering, one day over coffee, why this perfectly serviceable house never got any use. (My parents do some of their best thinking over coffee.)

“Well, there are a lot of trees with woodpecker holes in them,” my father offered. Maybe the wrens just didn’t need any additional housing.

“Maybe we’re putting it out too late,” my mother suggested. They put the birdhouse in the basement every winter and spent early spring in Florida.

So this year, just to be on the safe side, my parents left the birdhouse out all winter so it would be ready for the wrens first thing in the spring. But winter was hard on the old birdhouse and my father noticed the perch had fallen out.

“Maybe no one will use it because it doesn’t have a perch!” my mother reasoned, so my father set about finding a suitable dowel to replace the 50-year-old missing perch.

Dad took the old birdhouse down to his workshop in the basement. The dowel he’d found was a little too stout for the existing hole, so he laid the birdhouse on its back, got out his drill, and widened the hole a bit. Then he gave the dowel a whack with a hammer until it fit in just right.

Dad looked in the round door. The birdhouse was filled with nest.

“Maybe nobody’s using it because it’s too dirty,” my father thought. So dad flipped the birdhouse on its side, got out his drill again, and removed the screws so he could clean out the debris.

But as my dad started to lift the back, he heard a flapping noise.

“Oh no!” my father said.

Dad’s vision is not the best, so he called my mom for back-up.

“Jonie, come downstairs!” dad hollered. “I think there are bats in the birdhouse!” Mom came running and they carefully lifted the back off the birdhouse.

Three baby wrens looked up at my mom and dad.

“Oh no!” my mother said.

Dad quickly reassembled the birdhouse and they hung it back outside. Mom said she felt terrible. She knew those baby birds would likely be abandoned.

But a few days later, my mom saw the mother bird come out of the house and fly off. Later, dad heard the chirping of wrens coming from the house. Then one day it was quiet. My mom peeked inside. All the little birds had flown.

So now my parents have something new to wonder about as they have their coffee. Was mother wren gone while her three children were hauled down to the workshop? Did she return to the tree and find her house and offspring missing? Was she surprised by their miraculous return? And what about that fancy new perch?

My parents are still mulling this over, as they have their coffee. I think it’s good the old birdhouse is finally getting some use.

Carrie Classon’s memoir, “Blue Yarn: A Memoir About Loss, Letting Go, & What Happens Next,” was just released. Learn more at CarrieClasson.com.