Baby shower etiquette

Km • 27. Married 5 years. Our daughter Stella Claire is our entire world. Born Nov 15. 2015. Pregnant with #2 due in April.
If someone invites you to a baby shower (think close friend, co-worker or cousin), and you can't make it, does etiquette say you're supposed to send a gift? I have 11 girls from my list who can't make the shower and don't plan on sending anything.  If I was a guest, I would certainly send my regrets and a gift/card to a close friend if I couldn't come.