Today is Mother’s Day in the United States. To celebrate, here are 5 of the most interesting facts about orangutan mothers that you might not know.

Photo retrieved from SOCP
1. Female orangutans can have twins, though it is very rare.
2. Orangutan children have the longest childhood dependence on their mother of any animal in the world.

Photo retrieved from nationalgeographic.com / photograph by Erin Vogel
3. Orangutan mothers nurse their babies until they are about 6 years old.
4. Female orangutan offspring can stay with their mothers in their teens so that they can pick up mothering skills by watching their mother raise younger siblings.
5. Wild orangutan mothers are single parents and have a very close relationship with their offspring.