Turns out there is, in their own special way, even there's no evidence to prove it. Tootie is a creeper, Trixie Tang is a snob, Cindy loves Jimmy Neutron more, Molly is gothic/scary, Missy is very complicated to be with Timmy but Chloe maybe a spunky crazy girl so she cares for Timmy more then those girls.
This is the sign for caring for Timmy more