I was about 5 months pregnant with my second child the summer that I got an email I had been dreading. “Hey! Can you please pick up an extra day or two each week to help cover Erica’s days once she leaves? It would just be until your maternity leave. Thanks!”

At the time, I was working part-time at a small medical office and one of my coworkers was on her last 2 weeks before moving to a different job. She had given plenty of notice for a replacement to be hired and trained, but the company had dragged their feet and so far hadn’t done much to find a replacement. It was true that I was only working 3 days a week and could have added in a 4th or 5th day, and maybe could even have used the money. But I was relishing my long summer days off with my 18-month-old son, our last few months together before adding another baby and enjoying the slower pace for this pregnancy. My mother was also my childcare while I worked, a role she happily and selflessly took on, but had firmly stated that she only wanted to do 3 days a week (a stipulation I thought she had earned after raising her own two children). Admittedly, I was also a little annoyed that the responsibility for filling my coworker’s hours was being casually shifted onto me when there had so clearly been plenty of time to hire a replacement.

I had known this request was coming, but still, when the message came through I felt that familiar prickle of discomfort as my desire to set boundaries and my desire to be agreeable butted up against one another. There was once a time when my professional life was everything and I would have jumped at the opportunity to work extra and show how dedicated I was. After my first son was born though, my priorities shifted and I cut back to part-time. To me, reducing my hours had seemed like an obvious signal that I wanted more time with family, but what I didn’t expect was how often I would have to continue defining boundaries and asserting myself against others who viewed my “free” time as always up for grabs.

It was so tempting to be the yes-person, to say I would cover those shifts, Sure! No big deal, it’s just until the baby comes anyway. But I knew the temporary satisfaction I would feel at being available, at being a “good” employee, would fade the minute I had to find childcare for those extra days or miss out on summer fun with my sweet boy. I knew that the level of appreciation I would receive as I solved someone else’s problem for them would be minimal and the fight to maintain boundaries after breaking them would be huge.

I was lamenting to a friend about the challenge of finding a way to say no without seeming lazy or like a poor team member; Sorry, I really wish I could…. I would but I don’t have childcare….Let me see if I can work something out and I’ll get back to you… and instead of helping me minimize my discomfort with a polite and bendable boundary, she gave me the mantra that I now use every time I feel that urge to over-explain myself, apologize, or change the perimeters of my comfort zone. No is a complete sentence.

Extra shifts were just that, extra. I was a hardworking and dedicated employee when I was on the clock, but I was contracted for 30 hours a week and I didn’t owe explanations or apologies for wanting to stick to that. No is a complete sentence. The more I adopted this philosophy, the more I realized the same goes for obligations and events at school, church, friends, and family, or any other organization or people that asked for my time. Saying yes is fine until you actually want to say no. There is this insidious tendency among moms to feel that we must put our jobs or other responsibilities before our family time and mental health. Or that we must explain or apologize profusely if we choose to keep our personal time sacred. But no is a complete sentence. It is hard to say no, but it is even harder to make it through the day-to-day when we are overbooked and without boundaries.

I typed a simple I am not available for more hours at this time, took a breath, and hit send. No apologies, excuses, or compromises; and you know what? It wasn’t that bad. In fact, I felt relieved and even respected as my employer worked out a different solution and never made me feel any of the horrible things I had imagined.

Saying no is a difficult skill that must be practiced and refined constantly. But saying Yes to more than we want or can handle does not make us better professionals or people; in fact, it often makes us worse as we crumble under the strain of trying to maintain an impossible balance. Teaching our children to have a good work ethic is important, but modeling respect towards ourselves and our precious time by setting clear boundaries is even more crucial. So start practicing those no’s, Mama, and see how your life changes for the better.