Ya Lun and Xi Lun, the giant panda twins at Zoo Atlanta, will celebrate their second birthdays shortly, and Atlanta is invited.

The twins actually turn 2 on Monday, Sept. 3, but a party is planned for Friday, Aug. 31, with treats for the bears.

And for the humans? No goody bags. Just the satisfaction of watching the big gals unwrap their presents.

The twins will receive their gifts at 10 a.m. and 3 p.m. Friday, Aug. 31, at the Giant Panda Conservation Center. (The zoo reminds us that bears aren’t always punctual, and that the exact times will depend on the bears.)

The surprises usually come in the form of a nicely decorated box containing colorful multilayered ice cakes, built out of healthy edibles, such as bamboo, sweet potato and different fruits.

>> RELATED: Remembering when the twin panda cubs were just learning to walk

This time of year is a big one for birthdays, since mother Lun Lun turned 21 on Aug. 25, and father Yang Yang will turn 21 on Sept. 9.

Ya Lun and Xi Lun are the sixth and seventh offspring of Lun Lun and Yang Yang. Their older brothers and sisters include Mei Lan (born 2006); Xi Lan (born 2008); Po (born 2010); and Mei Lun and Mei Huan (born 2013).

They are the second set of twins born to Lun Lun, a remarkable achievement for this super-mom and for the zoo.

>> RELATED: A look back at when the panda twins were turning 1

The twin pandas at Zoo Atlanta, Xi Lun and Ya Lun, are approaching their first birthday on Sept. 3, 2017.

The zoo estimates that there are fewer than 1,900 giant pandas in China, and of these, more than 1,200 live inside nature reserves. Zoo Atlanta has supported programs on eight of these reserves and has helped support reforestation projects, conservation education programs, giant panda nurseries and field research programs.

Ya Lun and Xi Lun’s older siblings have all been shipped to China. The panda offspring all belong to the Chinese government, under the agreements that allowed their parents to be loaned to Zoo Atlanta in 1999.

EVENT PREVIEW

Panda birthday party

The panda twins will receive gifts at 10 a.m. and 3 p.m. Friday, Aug. 31. (Zoo Atlanta is open 9:30 a.m.-5:30 p.m. Friday.) $22.99 ($25.99 at gate); college students, $21.99 (only at gate); senior citizens (ages 65 and older), $18.99 ($21.99 at gate); children ages 3-11, $16.99 ($17.99 at gate); free for children ages 2 and younger; free for military. 800 Cherokee Ave. SE, Atlanta. 404-624-9453, zooatlanta.org.