Answer:
hummm theres this one song " sisters" by s2s and theres " my sister" by Reba mcentire
another one not directly realted to sisters but that could be about sisters bond is " because you loved me" by celin Dion
there are aslo alot of songs about friends out there that could realte to sisters somewhat
theres a few "kiddish" ones aswell but there not really directly about growing up or sisters theres " together we can " and " cheetah sisters " by the cheetah girls and " two voices one song" barbie. ( its about friends but the lyricks could go for sisters too)