$40 Bed and bath collection available. Navy Blue and Gray Stripe Kids Bathroom Fabric Bath Shower Curtain - Click to enlarge
Drapes/curtain rod outside, shower curtain/tension rod inside. Show to Nathan and see if it's worth the hassle.
Savvy Design Tip | Extra Long Shower Curtains | from Living Savvy
The teal shower curtain would be good for the bathroom because it helps incorporate the teal with the house. It is also simple and not to bold.
contemporary white & gray bathroom with two extra long shower curtains hung close to the ceiling making the bathroom look HUGE!... Beautiful Bathroom Inspiration: Contemporary Shower Curtain Ideas from Bathroom Bliss by Rotator Rod
Lego Star Wars shower curtain (PrintArtShoppe) - possibly contact for a 4.5' x 4.5' curtain in red for play area.
White, Black, and Silver/Gray Shower Curtain: Sequins, 72in x 72in #VictoriaClassics #Modern
Home Classics Ivy Fabric Shower Curtain
Nicole Miller Fabric Shower Curtain Teal Mosaic Lace Medallions Ombre Print 72-Inch by 72-Inch Shower Curtain Aqua Turquoise Gray Teal Grey White, http://www.amazon.com/dp/B01407448M/ref=cm_sw_r_pi_awdm_WSI3vb1PX251T
Shower Curtain in Navy, Coral Pink, Aqua, Gray Floral Standard and Extra Long Lengths 70, 74, 78, 84, 88 Let's make one in your colors!