But as same-sex couples became more visible over the past decade — and the women left the school, went into business together, started raising twins and discovered Kelly's breast cancer — they were ready to show their family to the world.
Kelly, 55, and Heether, 43, are among the growing number of gay couples living and raising children in Maryland and willing to say so. The number of same-sex couples in the state increased by 51 percent over the past decade, and more than a quarter of those couples are raising children, according to 2010 data released today by the U.S. Census Bureau.
"I am not dying afraid," said Kelly, who once lived in fear of what people would think of her same-sex household. She was diagnosed with breast cancer during the past year and resolved to be as visible with her family as any heterosexual couple. "I don't want to live that way, and I certainly don't want to die that way."
The number of same-sex couples in Maryland rose from 11,243 to 16,987 households, the Census said — a trend that has been reflected in other states. Lesbian households account for more than half of the gay households in Maryland, about 10,000.
Demographers said the change should be attributed to more accurate responses on census forms, rather than a rush of gay couples moving into the state.
"The most realistic explanation for such a large increase in the number of same-sex couples is increased acceptance and media campaigns that encouraged gay couples to be counted," said demographics expert Amanda Baumle, an associate professor of sociology at the University of Houston.
The census and gay-rights advocacy organizations such as the Washington-based Human Rights Campaign, Baumle said, developed a public relations campaign before the 2010 census forms were sent out to ensure that gay couples knew how to have their relationships counted.
The federal government's tally of same-sex couples, which is being released on a rolling, state-by-state basis, is especially significant for Maryland because of this year's emotional General Assembly debate over gay marriage.
A same-sex marriage bill cleared the state Senate this year, but was pulled from the House floor after leaders determined that they were a few votes shy of the number needed for passage.
Opposition to gay marriage in Maryland is largely due to strongly held religious beliefs. Black churches from Prince George's County and the Baltimore area led the push against the 2011 bill. Roman Catholic leaders also have opposed the measure, and Baltimore Archbishop Edwin F. O'Brien recently urged Gov. Martin O'Malley not to promote "a goal that so deeply conflicts with your faith."
But the governor said several weeks ago that he would throw his weight behind the legislation, renewing supporters' hopes for the 2012 General Assembly session. O'Malley is following in the footsteps of New York Gov. Andrew M. Cuomo, who helped push a similar measure through his state's legislature this year.
"Every 10 years, the census gives our state a chance to look in the mirror and see who we really are and not hide the reality," said Del. Mary L. Washington, a Baltimore Democrat who is gay and a supporter of marriage equality legislation.
Washington, who wrote her doctoral dissertation at the Johns Hopkins University on the census' influence on national identity, added, "It basically tells us what we've known for a very long time. Gay families are living right here, working right here, raising children right here. We are a part of the everyday life in the state of Maryland."
Del. Heather R. Mizeur, a Montgomery County Democrat who is gay, said the new census information shows that gay people live in all corners of the state. Every county in Maryland, as well as the city of Baltimore, showed double-digit growth in same-sex households over the past decade.
Rural Garrett County had the largest percentage increase — more than 200 percent — though the number of gay households is under 100.
"It's not just that we have pockets of gay people in the big three jurisdictions," Mizeur said.
Gay couples account for about eight of every 1,000 households in the state, according to the census data, collected in the spring and summer of 2010.
Gary J. Gates, a demographer at UCLA School of Law's Williams Institute, conducted a survey after the 2010 Census and concluded that it undercounts gay couples, who might identify themselves as roommates, by at least 15 percent. The new data, he said, might have other problems, because something as simple as a smudge on a form can make a respondent's gender inaccurate — and that could balance out the under-reporting.