We have 2 kids, 18 & 14. One of the rules in our family is, you have to engage in at least one extra curricular activity in every year of school. Our kids picked music (yeah, I play 4 instruments and may have pushed a bit). So, Allie plays sax and clarinet, Andy plays piano, guitar, drums and marimba.
In our home is an upright piano, electric piano, bass guitar, 3 electric guitars, classical guitar, banjo, saxophone, clarinet, drums, and probably some stuff I forgot.
I believe that playing an instrument and/or playing competitive sports instills a certain mind set in folks. I think it helps a mind to think outside the box and/or instills a drive for people.
Could be the which came first, chicken before the egg scenario. Would they have done so anyway? Probably not, for me personally I wanted to be proficient at particular instrument's. Can I think outside the box? You betcha! Do I think it helped? Yep, in my opinion music and/or competition is a situation that keeps opening your mind and testing your ability. Of course this is only my opinion. Good Luck!