Congratulations are in order for Mommy, a Galápagos tortoise and a longtime resident of the Philadelphia Zoo, who recently became a first-time mother at the estimated age of 100.

Mommy, who has lived at the zoo since 1932, laid 16 eggs in November. Four of them have since hatched — the first successful hatching for her species at the zoo, which opened in 1874.

She had help, of course — from Abrazzo, a male tortoise who is also estimated to be about a century old.

Mommy and Abrazzo, both members of the Western Santa Cruz subspecies, are the oldest animals at the Philadelphia Zoo. But Galápagos tortoises can live as long as 200 years, the zoo said, putting them squarely in middle age.

The first hatchling emerged on Feb. 27, the zoo announced on Thursday. The others followed within days, with the last one hatching on March 6.

The hatchlings, none of which have been named, are expected to be on view to the public starting on April 23, the zoo said. They are doing “fantastic,” according to the zoo’s director of herpetology, Lauren Augustine. (Herpetology refers to the study of reptiles and amphibians.)