Birthdays
Even more specific information was found to analyize Chibiusa and Hotaru's exact days of birth. This information is also related to their zodiac signs (Cancer [Chibiusa] and Capricorn [Hotaru] respectively).June 30
Those born on June 30th are quick-witted, intuitive, emotionally approachable, and respond to problems with helpful solutions. Due to Cancer's trait of easily reading others' emotions, a person born on this day can prevent a negative event from occuring. These people are normally very rational, and this keeps them from over-dramatizing situations. People born on June 30th find great enjoyment in sharing their ideas, and listening to the ideas of others. They are normally quite curious, and have good memories, which makes them outstanding students or teachers. People born on this date have a deep desire to fulfill their creative potential. With a combination of intellect and imagination, they normally possess the ability to have great artistic talent. Compared to other Cancers, June 30th people are more relaxed. Socially, they are outgoing, charming, and personable. However, due to their ruling planet, people born on June 30th are still subject to the ever-changing mood swings of Cancers.
My Thoughts: Everything that doesn't fit for Chibiusa in the regular Cancer description is made up for in this analysis. I feel the pink-haired girl hits on every one of these points. The emphasis on the arts is important, because Chibiusa's favourite school subject is Manuel Arts, and in the anime, she is often seen drawling pictures. The stress on being more rational and relaxed than most Cancers is an important part, which fits Chibiusa well. The social aspect of the young girl's character is also explained perfectly.
January 6
Those born on January 6th are a paradox of being outwardly pragmatic, yet inwardly compassionate and idealistic. They are practical visionaries, and extend their humaness through duty. People born on this day are ambitious and tenacious on one hand, and innately spiritual and philosophical on the other. They have a strong love for the arts and poetry, and may have artisic potential themselves. People born on January 6th are peace-loving, and are not ones to go looking to pick a fight. Although they are amicable, this does not translate into a weakness. Since Capricorns are such hard workers, they desire recognition and appreciation for their accomplishments, and cannot stand being taken for granted. When they are feeling hurt or insecure, they activate their inner defenses. Related to this, when people born on this day are disappointed, they will fake a smile to keep up appearences. Compared to other Capricorns, people born on January 6th are more emotional, caring, responsive, and practical. They also have a strong domestic side that craves for a strong home and family life.
My Thoughts: A paradox of being practical but compassionate, I think that's a very fair analysis of Hotaru's character. During the S season, Hotaru had to seem rather aloof, because her possession pushed everyone away from her. However, when Chibiusa doesn't let this problem affect their friendship, Hotaru allows her only friend to see the good person she is on the inside. Having the courage to surrender your life for the hopes of a saved world, Saturn truly shows her humanity through her devotion to her grim duty as a soldier of Saturn. The overall feel of opposites fits well with Hotaru, because Saturn brings to Hotaru the destiny and obligations of being a soldier of the solar system. Hotaru doesn't seem as keen on the arts as Chibiusa, but she does learn to play the violin from her Michiru-mama in the manga, and enjoys reading (and writing to an extent) in both anime and manga versions. This young girl desires peace for her solar system, just like the rest of her fellow senshi. Hotaru can still put on a strong aloof wall when there's a problem in her life. She doesn't seem like the type to tell others about her feelings, because she doesn't want to be a burden. I could see her putting on a smile to cover up the pain in her heart. However, I think eventually she would break down and confess her concerns, because she's a smart girl, and her princess has taught her that no one has to rely on themselves. All the sailor senshi are friends, and together, there is no problem they can't solve.
Information relating to this and the zodiac are taken from "What Your Birthday Reveals About You" by Phyllis Vega.