NATIONWIDE — Sesame Street has reintroduced a Muppet that it hopes will shine a light on childhood homelessness.

Lily was introduced to the PBS neighborhood seven years ago in a special about childhood hunger.

Now, Lily is back, and this time, the storyline follows her family, who lost their home and have to live in shelters and with friends.

Sesame Street is telling Lily's journey through homelessness and transition in a series of YouTube videos. Lily won't appear in televised episodes.

"We applaud Sesame Street's efforts to shed light on this humanitarian crisis, and at the same time, support children and families who are homeless and the providers who serve them," Paul Webster, co-chair of the National Coalition for Homelessness Solutions, said in a statement. "Family homelessness has increased significantly over the past 10 years, yet they are the 'hidden homeless' as families are often found staying on people's couches or in motel rooms."

The number of children who are dealing with homelessness has increased between 70 to 100 percent during the past decade, the National Coalition for Homelessness Solutions statement said, citing federal education and Health and Human Services numbers.