Grenadian authorities are asking for help locating Waddell, who her family said went missing Wednesday after going down to the water near Grand Anse Beach for a swim.
Friends say they are staying strong and hoping for the best as search efforts continue.
"She's an amazing person, and we want to bring her home," said Amanda Romano-Harmon, a family friend of Waddell's. "It seems that she went down to the pier and left her towel on the pier and went for a swim."
Romano-Harmon and her husband, Shawn, have known Waddell and her husband, Cailen, for decades. Their husbands were college roommates, and the families recently went camping together.
She described Waddell as adventurous, free-spirited and someone who easily connected with others.
"She'll see kids playing in the park as she's walking or exercising or whatever, and she'll start kicking the ball with them. Everybody's a friend for Liz," Romano-Harmon said.
The bond between the two families runs deep, Romano-Harmon said.
"Our daughter is 16, and she refers to them as her aunt and uncle, because we're just that close," Romano-Harmon said.
Romano-Harmon said she and her husband were on a work trip earlier this week when they learned about her disappearance.
"The tone was getting a lot more serious. And he was getting a little bit upset, and, he got off the phone, and he said, that was Cailen. Liz went missing at noon today," Romano-Harmon said.
Friends said Cailen Waddell has praised Grenadian authorities for their efforts during the search.
Now, family and friends are asking anyone with information to come forward.
"If you have any, any information, no detail is too small. We are trying not to leave any stone unturned," Romano-Harmon said.
Romano-Harmon said her husband plans to travel to Grenada on Monday to help Cailen Waddell with search efforts.
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