The attacks did not appear to be related.
In the first incident, a 2-year-old girl was bitten in the 4800 block of Gransback Street in the Feltonville section of Philadelphia around 2:00 p.m.
The girl was taken to Saint Christopher's Hospital for Children.
Medics reported the girl was breathing normally and was conscious.
The other incident happened around the same time in the 10000 block of Dedaker Street in the Somerton section.
Medics arrived to find a 12-year-old girl had been bitten in the face. She was also taken to Saint Christopher's Hospital for Children.
There is no word yet on what provoked either attack.