Tina Fey once said that being a mother made her so very tired, and so very happy. Leave it to Tina to sum up motherhood so exactly.

Being a mother is living in a constant state of yin-yang. Actually, there may be more yin than yang. Or maybe it’s more yang than yin. What I’m trying to say is, there are phases of motherhood – if not the entire journey itself – where the work feels like it outpaces the holidays.

Newborns look adorable in white onesies. Their tiny hands and feet, and the tiny nails on them, seem like ten tiny miracles. Every yawn, blink and pucker presents as so much more than a reflex. It’s as if science and art Big-Banged in your living room and deposited a creature worth documenting on a second-by-second basis in your lap.

But newborns don’t know how to sleep, or eat, without out very attentive, patient, incessant coaching. Those onesies often stain, thanks to diapers that don’t do their job. There is no more personal space or personal time. A newborn demands every inch of a mother’s body and every minute of a mother’s waking – and non-waking – life.

Those newborns grow into toddlers that learn how to walk into your arms, and to say your name and tell you they love you. The toddlers grow into preschoolers that come home with pictures they have colored of you two holding hands in front of your house. The preschoolers board a bus one day and learn to write words, sentences and paragraphs that create stories about their favorite adventures with their family.

But toddlers put things into their mouths that prompt emergency baths or trips to the emergency room. Preschoolers learn to use scissors to cut paper and also their own hair. Elementary-schoolers want to host play dates and then look to you for ideas of what to play with their date.

Your child becomes a young adult with her own ideas and interests. She shares them with you, and pretends like she isn’t interested in your opinion even as she begs you for it. You feel him watching over your shoulder for guidance on how to drive, or how to dance, or how to decide.

But young adults slam doors and roll eyes. They treat you like a fool even as they ask you for a favor. You feel them watching over your shoulder, lying in wait for the next mistake you make or embarrassing thing you say.

They come back to you when they leave you. They become your friend again when they stop being your roommate. They learn to miss you.

But then they lose a love or a job. Their rent goes up, their spirits plunge. They get sick, or they get sick of trying. The problems you are asked to solve are of a different magnitude.

The long nights. The repeated reminders. The worry. The fights. Those reminders again. The threats. The heartaches. Let me remind you one more time, now with an escalated threat.

All of that work is paid off in glimmers of hope, whispers of thanks, signs of appreciation. An unexpected hand slipping into yours. A well-timed squeeze around your neck. A smile beamed directly at you. A bad habit broken. A new skill learned. A storm weathered. A challenge confronted, and then overcome.

Mothers so need their moments of space, both physical and emotional, that acknowledging that need has become a trending theme of social media. There are hashtags and memes and viral quotes dedicated to the relief mothers need. Mothers talk of girls’ night out, yearn for trips alone to the grocery store, joke about going to the bathroom with the door closed.

But you have never heard a mother say she’d trade her child for a lifetime of full nights’ sleep, or years of peaceful dinners, or uninterrupted afternoons with a book. Her child is fundamental to who she is. Her child is her lifetime achievement award.

She’ll rest when she can’t get any happier.

Abby Diaz grew up in Falmouth and lives there again, because that’s how life works. She blogs at whatsleftover.com. Follow Abby on Twitter: @AbbyDiaz1.