Is the assignment a persuasive essay? A narrative essay?
Okay, if it's narrative...
Tell about one crucial moment in your life (either as a daughter or as a mother) that defined "motherhood" for you. Perhaps focus on one crucial moment you experienced as a mother that gave you insights into what *your* mother went through as a parent.
Tips: Focus on ONE SPECIFIC moment. Be clear and detailed; put us in the picture. Don't state your "thesis" (although you should definitely *have* a point you want your reader to get while reading this essay). Use sensory detail, comparisons, analogies, etc. to put us in the moment.
If it's persuasive...
God, there are a zillion "hot-button" topics having to do with motherhood about which you could present an argument:
Formula or breastmilk?
TV or no TV?
AP or CIO?
Natural or c-section?
Vax or non-vax?
Extended breastfeeding vs. "Not if they're old enough to ask"
Homeschool or public school?
Stay at home or work?
Day care or stay home?
I could go on. If you choose one of those, here's a useful format (a basic, but useful, game plan)
Paragraph I - Intro
Body paragraph I - State basic position on any above issue.
Body paragraph 2 - State the "On the other hand..." other side.
Body paragraph 3 - The ultimate bottom line, the "Even though..."
Hope this helps.