3) Farrah and Sophia
Farrah was also on the first season of 16 & Pregnant and later on Teen Mom, but seemed busy with everything but baby Sophia at the time. Above you can see what she looked like at that time.
Sophia is now also thirteen and old enough to have her septum pierced and her hair dyed (although opinions are divided on this). They regularly visit events together these days and Sophia is completely in her emo/goth phase.