Alicia Marquez is Diego and Daisy's cute and very beautiful 11 year old tomboy sister and resident computer whiz.
She adores her little brother and is amazed at his natural gift for communicating and bonding with animals. Despite her cuteness and beauty, Alicia is protective of Diego and warns him of approaching dangers via his video watch from her monitoring position at the Rescue Center. She is the only one in Diego's family with green eyes while the other members of the family have brown eyes.
Alicia is mostly a peach-brown color. She has chest-length brown hair and grayish-green eyes. For the first 3 seasons, she is often shown wearing a pink hair clip, a red short-sleeved t-shirt, greenish-grey cargo shorts, a tan vest with the Rainforest Rescue Center logo on the left side, a red bracelet, yellow ankle-high socks and light gray and white shoes. Her ears are pierced with baby blue pearl ear studs. Sometimes she wears a rescue pack like Diego. When swimming, she wears a red and yellow one-piece swimsuit with the Rainforest Rescue Center logo on the left side. In the fourth season of Go, Diego, Go!, She wore a blue short-sleeve hoodie with a light blue undershirt, a blue bracelet, khaki cargo shorts, white socks and blue shoes.