For Ralph and Shamita Etienne-Cummings, the suburbs have long held a certain allure — especially since 2010, when their son, Blaze, was born and Mr. Etienne-Cummings’s mother moved into their 1876 rowhouse in Washington, D.C.

“Space became more of a premium,” Ms. Etienne-Cummings said. Her husband, she explained, is “from Seychelles; I’m from India. Culturally, we always have family that lives with us.”

But the benefits of living outside the city — having a big backyard and a bigger house — couldn’t compete with convenience of their life in Washington’s Logan Circle neighborhood, on a blocklong street coveted for its historic homes and central location.

“Our son grew up walking everywhere with his grandmother,” said Ms. Etienne-Cummings, 52, a lawyer. “We really wanted to stay in our neighborhood, but definitely needed more space, and that was difficult to do in an area that’s already filled up.”