Which direction is the right one?

K is very artistic, in multiple ways.  She has developed quite the skill for painting. Musically she can hold a beat, carry a tone fairly well, and gets the hang of most instruments.  Her imagination is strong and she very much enjoys making up her own stories.  But are all 3 year olds like this?  is mine that talented? At what point as a parent should we make the decision to enroll our child in formal lessons for something we think they have talent (and an interest) in?  Do we wait for them to tell us they want to know more? or by then is it too late? T along with his Father and brother have tons of musical talent.  He plays piano, guitar, bass, harmonica, as well as sings and writes his own music.  His brother played piano and guitar and wrote and sang his own music. His dad played piano.  This is in addition to my grandfather who was a working musician at the age of 10.  playing in bars jazz bands and making more $ than his father. he even managed to stay out of two wars by being in the military bands.  T and his dad and brother are skilled writers.  He dabbled in art as a youngster and his brother went to college for art.   Do I react to my instinct that our kid has talent in these areas to start her in lessons? Piano? Violin? Guitar? Or do I sit back, wait, and let her express her interests?