This is a fun set of pjs, too bad it's in little kids sizes only. This is by a new in 2014 company "SGI Apparel Group". Notice what their paper tag looks like, a disk with thumbs-up modern Sonic. The top is a short sleeve, with red collar & sleeve tips. It has an extra red sleeve stripe. The art is newer running/angle Sonic. The pants have scattered modern stock arts & logos with some checkers. This was found at Ross for 7.99. However, Ross does not get its own merchandise. It is a 'clearing store' for things that did not sell out at other retailers*.

So, while you can look for the set at your local Ross, it may or may not be there, depending on how well this did in its original selling place. 
*This doesn't mean the item is junky or "did bad", it just means if it shows up at Ross, 100% of them didn't sell out, which is both common & normal in retail.