They spoke to 3,000 military personnel and family members Wednesday morning and then attended a baby shower for 40 pregnant women whose husbands are in the service.
"We want everyone in this country to know just how extraordinary our military families really are," Michelle Obama said.
They also delivered gifts to the expectant moms and lifestyle guru Martha Stewart headed up a scrapbooking session.
Sugarland bakery in Chapel Hill was selected to bake a cake for the event. In keeping with the shower's vintage toy theme, the bakery created a life-sized red wagon filled with edible vintage toys.
Surgarland Executive Chef Katrina Ryan says she's confident the 75-pound cake will live up to expectation but admits she still has butterflies.
"I'm confident in the deliciousness of the cake, but you always, you always want to impress someone you respect as much as either Mrs. Obama or of course, Martha Stewart," Ryan said.
The cake will begin its journey to Camp Lejeune Wednesday morning. It's half French vanilla buttermilk and half dark chocolate.
The event came a day after Obama and Biden announced the Joining Forces initiative to support military families, who often are challenged by absent spouses and frequent movement.
Obama and Biden will continue their tour with stops Wednesday and Thursday in Texas, Colorado and Ohio.