National Zoo’s lion cubs made their public debut today, and your heart melt.

They passed the swim test.

Now it’s May roaring in like a lion.

Here’s a video of the Smithsonian’s lion cub half-siblings meeting, battling. Happy Friday, you guys.

The due date for Shera, another female lion at the Zoo, is “imminent,” according to the Zoo.

The cubs’ sex has yet to be determined as their genitalia isn’t fully formed yet, according to the Zoo.

“The first few days of a lion cub’s life are very fragile,” Rebecca Stites, an animal keeper at the Great Cats exhibit, said in a release.

Former DC Rollergirl Kristen Clark has worked at the National Zoo since 2005, volunteering there for several years before landing her dream job. Clark is assigned to the Great Cats & Bears unit, where she is one of two primary lion keepers. During her work day, which usually begins at 6:30 a.m., she’s responsible for looking after the lions, caracals, coatis and sometimes the prairie dogs. I was lucky enough to be able to spend some time with her and her charges last Sunday.

That’s right: it’s the complete set of National Zoo lion cub collectible identification cards!

In this video, National Zoo Great Cats curator Craig Saffoe explains why taking care of the National Zoo’s lion cubs — who had a limited debut this weekend — involves actually involves more work than just sitting there and fawning over how freakin’ cute they are.