It looks like one of Sony's latest creations, the Xperia S, could be getting a little brother at next week's Mobile World Congress, according to a series of leaked pics. Sixteen crystal-clear images show the new sibling -- none other than the previously seen ST25i, aka Xperia U or Kumquat -- snuggled up to the Xperia S. As it appears, the handset will likely be a lower-end offering in the Xperia lineup: it's said to feature a 3.5-inch FWVGA (854 x 480) Reality Display, a 1GHz dual-core CPU, Exmor R sensor with 720p video capture and a tiny user-replaceable 1,290mAh battery. Oh, and Android 2.3.7 is rumored, though the rumor specifically mentions it will soon be upgraded to ICS. If these whispers turn out to be accurate, the U will likely be pitched as a smaller and less expensive option for fans of the Xperia S's design. Also, we don't foresee the device's Sony Ericsson branding to make an appearance at the show, given the two companies' recent divorce. To check out the full suite of comparison pics, check out the source link below.