Slumber parties are always a party favorite for tween and teen girls! Sleepover/Slumber Party Birthday Party Supplies, Sleepover Party Favors and Party Decorations. Invite all the friends over for a sleepover bash! Have a fun and enjoyable sleepover / slumber party (if they sleep) with this adorable sleepover party (slumber party) theme. Also be sure to check out our line of sleepover party color coordinating solid color partyware, balloons and decorations.