PUTNAM COUNTY, Fla. -- After four excruciatingly difficult weeks for the family of Haleigh Cummings, the missing girl's father and his girlfriend announced their plans to wed, saying Haleigh would want it.

The 5-year-old Satsuma girl was last seen on the night of Feb. 9 when Misty Croslin, her father's now-fiancée, put the child to bed.

A month later, there has still been no sign of Haleigh even though investigators said they have checked out hundreds of leads and tips.

On Monday, Channel 4 talked with Croslin about her and Ronald Cummings' plans to marry. The 17-year-old hasn't smiled much since Haleigh's been gone, but she was beaming as she went into the courthouse to get a marriage license with Haleigh's dad.

Croslin smiled as she showed her engagement ring and talked about Cummings' surprise proposal.

"Last night at Chili's he got he down his knees and said, 'Will you marry me?'" Croslin said.

Haleigh's father said nothing as he and Croslin left the courthouse. However, Croslin told Channel 4 they are tying the knot because of Haleigh.

"Everybody's probably going to take this marriage thing the wrong way, but it's not. Everything's still focused on Haleigh. This is what Haleigh wanted. She's always talked about, and even if she's not with us, she is still with us," Croslin said.

The 17-year-old's mother, Lisa Croslin, accompanied the couple into court because she had to give her permission because of Croslin's age.

"They've been trying to get me to do it for like five months and I told them, 'You need to wait until you're 18.' But now that everything is going on … just let them do it. I know they love each other and they will be together," said Lisa Croslin.

Misty Croslin said if Haleigh were home, she would be thrilled about the engagement and that the girl would insist on having a new ring of her own.

"If I have something, she wants it. If we buy something for me, we buy something for her. Our shoes -- me and Haleigh had the same pair of shoes. Me and her pretty much tried to do everything together," Misty Croslin said.

She was the last person who saw Haleigh 28 days ago when she tucked her into a toddler bed in her room. When Croslin she awoke to use the bathroom, she saw Haleigh was gone.

Since then, the teen has been scrutinized by the public and questioned multiple times by police.

"I just want to let everybody know that I was home because I did pass my lie detector test saying that I was home," she said.

She said she has always treated Haleigh like family, and soon they will be family.

"Everybody knows that I love Haleigh and Ronald and Junior," Croslin said. "I want a family just like Haleigh wanted."

Anyone who has any information that could help find Haleigh is asked to call Crimestoppers at 888-277-TIPS.