Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. By signing up, you confirm you are 16+, will receive newsletters and promotional content and agree to our Terms of Use and acknowledge the data practices in our Privacy Policy. You may unsubscribe at any time. Humans often announce the biological sex of their offspring before the baby even enters the world. For bald eagles, the process can take a bit longer. After nine weeks, Friends of Big Bear Valley (FOBBV) announced on Tuesday that Jackie and Shadow’s 2026 chicks are likely a boy and a girl. The two chicks hatched in early April. Their names, Sandy and Luna, were bestowed on May 1. Now we know that Sandy is a female and Luna is male. Or at least we can confidentially guess. FOBBV, the non-profit who runs Jackie and Shadow’s 24/7 livecam, closely observed the duo since birth and noted traits that offered clues to the birds’ sexes. Luna (L), Sandy (R) in their nest on June 9. …